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Full-Text Articles in Other Astrophysics and Astronomy

Modeling Hot Jupiter Atmospheres For The Classification Of Low Abundance Molecules, Mika Brown May 2026

Modeling Hot Jupiter Atmospheres For The Classification Of Low Abundance Molecules, Mika Brown

Physics Undergraduate Honors Theses

Transmission spectroscopy is a powerful method for studying exoplanet atmospheres. With the recent launch of the James Webb Space Telescope (JWST), several molecules have been successfully detected in hot Jupiter atmospheres at an unprecedented level of precision with transmission spectroscopy. To better understand current detection capabilities and limitations, this project used machine learning techniques to determine which molecules are currently identifiable at the spectral resolution and wavelength range of JWST’s NIRSpec instrument in PRISM mode. A large synthetic dataset of transmission spectra was first generated using the petitRADTRANS radiative transfer Python package. The resulting spectra were then used to train …


A Spectroscopic Survey Of Atmospheres Of Super-Earths, Luke Brust May 2025

A Spectroscopic Survey Of Atmospheres Of Super-Earths, Luke Brust

Honors Theses

Recent research has made it possible to use spectroscopy to analyze the composition of the atmospheres of exoplanets, planets that orbit other stars. Most projects thus far have focused on the atmospheres of gas giants, as it is less challenging to observe them with available equipment. This project studies the atmospheres of four Super- Earths, planets that have a mass greater than the Earth but smaller than Neptune. This is accomplished by processing the raw spectroscopic data from the Hubble Space Telescope and modeling the atmosphere using the program 𝝉-Rex3. This survey found clear results from two of the selected …


From Stars To Moons: Investigating Stellar Rotations, Planetary Interactions, And Exoplanetary Prospects, Rosario Cecilio-Flores-Elie Sep 2024

From Stars To Moons: Investigating Stellar Rotations, Planetary Interactions, And Exoplanetary Prospects, Rosario Cecilio-Flores-Elie

Dissertations, Theses, and Capstone Projects

The thesis is divided into two key sections. The first chapter presents the results of analyzing TESS light curves for 99 targets within the Carina-Near moving group. By deriving rotational periods, this analysis supports stellar age estimation, contributing to the broader efforts of the Backyard Worlds: Planet 9 citizen project in determining age parameters for 89 newly identified systems, including ultracool dwarf companions. These findings enhance our understanding of stellar rotation and evolution, offering new insights into the development of secondary co-moving objects like brown dwarfs.

The second chapter investigates planet-moon interactions within our solar system by examining mass ratios, …


Identifying And Analyzing Multi-Star Systems Among Tess Planetary Candidates Using Gaia, Katie E. Bailey May 2023

Identifying And Analyzing Multi-Star Systems Among Tess Planetary Candidates Using Gaia, Katie E. Bailey

Electronic Theses and Dissertations

Exoplanets represent a young, rapidly advancing subfield of astrophysics where much is still unknown. It is therefore important to analyze trends among their parameters to learn more about these systems. More complexity is added to these systems with the presence of additional stellar companions. To study these complex systems, one can employ programming languages such as Python to parse databases such as those constructed by TESS and Gaia to bridge the gap between exoplanets and stellar companions. Data can then be analyzed for trends in these multi-star exoplanet systems and in juxtaposition to their single-star counterparts. This research was able …


A Comparison Of Exotic And Pyraf In Analyzing Exoplanet Transits, Kailei A. Gallup Jun 2022

A Comparison Of Exotic And Pyraf In Analyzing Exoplanet Transits, Kailei A. Gallup

Physics

In this paper we discuss the data analysis processes using PyRaf, a Python-based version of IRAF, which is one of the most commonly used coding softwares in the astronomy community, as well as the analysis process using EXOTIC. Additionally, we will compare the outcomes from each process to determine if either has significant benefits over the other.


Information Entropic Content Of Astrophysical Spectra: Applications To Cosmology And Astrobiology, Sara Vannah Jan 2022

Information Entropic Content Of Astrophysical Spectra: Applications To Cosmology And Astrobiology, Sara Vannah

Dartmouth College Ph.D Dissertations

Astrophysics faces two critical challenges: the difficulty of observing very distant targets and the difficulty of interpreting science in diverse and often extreme environments that have not been replicated on Earth. In this thesis, we discuss two types of spectra — one from early universe cosmology and one from astrobiology — where improvements in telescope technology are just ushering in a wave of precise observations, addressing the first challenge. This accelerates the need for a solution to the second challenge. Traditional methods for analyzing these two spectra rely heavily on unsettled science, biasing results to match the input assumptions. In …


Investigating Signs Of Orbital Decay In The Tres-1 Exoplanetary System, Amanda F. Wester Jan 2022

Investigating Signs Of Orbital Decay In The Tres-1 Exoplanetary System, Amanda F. Wester

Honors Theses and Capstones

Transit observations of exoplanetary systems can be used to investigate orbital decay. TrES-1b is an exoplanet hypothesized to be experiencing orbital decay due to observed transit timing variations (TTVs) [12]. Numerous transits must be observed to establish a long term pattern to conclusively determine if the planet’s orbit is decaying. Measurements were made using the UNH Observatory where 2 transits were observed of the TrES-1b transiting system on February 27, 2022 and March 5, 2022. A CCD camera was used to image the transit and capture calibration images. The software AstroImageJ (AIJ) was used to calibrate the images and perform …


Searching For Trends In Atmospheric Compositions Of Extrasolar Planets, Kassandra Weber, Paola Rodriguez Hidalgo, Adam Turk, Troy Maloney, Stephen Kane Sep 2019

Searching For Trends In Atmospheric Compositions Of Extrasolar Planets, Kassandra Weber, Paola Rodriguez Hidalgo, Adam Turk, Troy Maloney, Stephen Kane

IdeaFest: Interdisciplinary Journal of Creative Works and Research from Cal Poly Humboldt

No abstract provided.


Observations And Light Curve Analysis Of Transiting Extra-Solar Planets, Clark M. Holcomb Dec 2016

Observations And Light Curve Analysis Of Transiting Extra-Solar Planets, Clark M. Holcomb

Electronic Theses and Dissertations

The purpose of this research was to perform the procedures to study transiting exoplanets in their entirety, from the data collection process to determining physical characteristics and orbital properties. The research was conducted with two telescopes of different sizes (16” and 12”) at multiple sites in order to refine the detection process. Both Maxim DL and Mira Pro x64 software were used to process the resulting images. The PHOEBE program was used to model the data to determine the properties of the exoplanets, which were then compared to the results obtained by other astronomers. The data collection process as well …


Exoplanet Research: Differential Photometry For Kepler 6b, Garrett T. Benson, Charlotte Alexandra Olsen Oct 2016

Exoplanet Research: Differential Photometry For Kepler 6b, Garrett T. Benson, Charlotte Alexandra Olsen

IdeaFest: Interdisciplinary Journal of Creative Works and Research from Cal Poly Humboldt

No abstract provided.


Fundamental Parameters Of The Lowest Mass Stars To The Highest Mass Planets, Joseph C. Filippazzo Sep 2016

Fundamental Parameters Of The Lowest Mass Stars To The Highest Mass Planets, Joseph C. Filippazzo

Dissertations, Theses, and Capstone Projects

The physical and atmospheric properties of ultracool dwarfs are deeply entangled due to the degenerate effects of mass, age, metallicity, clouds and dust, activity, rotation, and possibly formation mechanism on their observed properties. Accurate fundamental parameters for a wide range of substellar objects are crucial to testing stellar and planetary formation theories. To determine these quantities, we construct flux-calibrated spectral energy distributions (SEDs) for 234 M, L, T, and Y dwarfs and calculate bolometric luminosity (Lbol), effective temperature (Teff), mass, surface gravity, radius, spectral indexes, synthetic photometry, and bolometric corrections (BCs) for each object. We use …


Characterizing Exoplanet Host Star Atmospheres Using Spectroscopy, Kristen Fahy Aug 2016

Characterizing Exoplanet Host Star Atmospheres Using Spectroscopy, Kristen Fahy

STAR Program Research Presentations

Exoplanet discovery is an exponentially growing field which is allowing scientists to discover new worlds beyond our own solar system. The aim for this research project was to specifically look at the stellar activity of host stars to determine if it is affecting the output data of target exoplanets. Previously, astronomers understood that stellar activity could influence the detection of new planets, but until now nobody has studied how it may specifically affect the planetary transit spectrum. By analyzing transit spectroscopy plots, I was able to match specific wavelengths corresponding to chemical signatures of the host star to determine if …


Atmospheric, Orbital, And Eclipse-Depth Analysis Of The Hot Jupiter Hat-P-30-Wasp-51ab, Andrew Sd Foster Jan 2016

Atmospheric, Orbital, And Eclipse-Depth Analysis Of The Hot Jupiter Hat-P-30-Wasp-51ab, Andrew Sd Foster

Honors Undergraduate Theses

HAT-P-30-WASP-51b is a hot-Jupiter exoplanet that orbits an F star every 2.8106 days at a distance of 0.0419 AU. Using the Spitzer Space Telescope in 2012 (Spitzer Program Number 70084) we observed two secondary eclipses at 3.6 and 4.5 μm. We present eclipse-depth measurements of 0.177 ± 0.018 % and 0.247 ± 0.024 % and estimate the infrared brightness temperatures to be 1990 ± 110 K and 2080 ± 130 K for these two channels, respectively, from an analysis using our Photometry for Orbits, Eclipses, and Transits (POET) pipeline. These may be grazing eclipses. We also refine its orbit using …


Exonest: Bayesian Model Selection Applied To The Detection And Characterization Of Exoplanets Via Photometric Variations, Ben Placek, Kevin H. Knuth, Daniel Angerhausen Oct 2014

Exonest: Bayesian Model Selection Applied To The Detection And Characterization Of Exoplanets Via Photometric Variations, Ben Placek, Kevin H. Knuth, Daniel Angerhausen

Physics Faculty Scholarship

EXONEST is an algorithm dedicated to detecting and characterizing the photometric signatures of exoplanets, which include reflection and thermal emission, Doppler boosting, and ellipsoidal variations. Using Bayesian inference, we can test between competing models that describe the data as well as estimate model parameters. We demonstrate this approach by testing circular versus eccentric planetary orbital models, as well as testing for the presence or absence of four photometric effects. In addition to using Bayesian model selection, a unique aspect of EXONEST is the potential capability to distinguish between reflective and thermal contributions to the light curve. A case study is …