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Description
The LOw Frequency ARray (LOFAR) is a new and innovative radio telescope designed and constructed by the Netherlands Institute for Radio Astronomy (ASTRON). LOFAR unique capable of operating in very low frequencies (10-240 MHz) and consists of an extensive interferometry array of dipole antenna stations distributed throughout the Netherlands and

The LOw Frequency ARray (LOFAR) is a new and innovative radio telescope designed and constructed by the Netherlands Institute for Radio Astronomy (ASTRON). LOFAR unique capable of operating in very low frequencies (10-240 MHz) and consists of an extensive interferometry array of dipole antenna stations distributed throughout the Netherlands and Europe which allows it to achieve superb angular resolution. I investigate a part of the northern sky to search for rare radio objects such as radio haloes and radio relics that may have not been able to have been resolved by other radio telescopes.
ContributorsNguyen, Dustin Dinh (Author) / Scannapieco, Evan (Thesis director) / Butler, Nathaniel (Committee member) / School of Earth and Space Exploration (Contributor) / Department of Physics (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
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Description
Radio astronomy is a subfield in astronomy that deals with objects emitting frequencies around 10 MHz to 100 GHz. The Low Frequency Array (LOFAR) is a array of radio antennas in Europe that can reach very low frequencies, roughly between 10-240 MHz. Our project was to image and clean a

Radio astronomy is a subfield in astronomy that deals with objects emitting frequencies around 10 MHz to 100 GHz. The Low Frequency Array (LOFAR) is a array of radio antennas in Europe that can reach very low frequencies, roughly between 10-240 MHz. Our project was to image and clean a field from LOFAR. The data was a 10 degree square in the sky centered at a right ascension of 10:19:34.608 and a declination +49.36.52.482. It was observed for 600 seconds at 141 MHz. To clean the field, we had to flag and remove any stations that were not responding. Using a program called FACTOR, we cleaned the image and reduced the residuals. Next we checked the validity of our sources. We checked positional offsets for our sources using the TGSS survey at 150 MHz, and corrected the declination of our LOFAR sources by a factor of 0.0002 degrees. We also fixed the LOFAR fluxes by a factor of 1.15. After this systematic check, we calculated the spectral index of our sources using the FIRST survey at 1435 MHz. We plotted this spectral index against LOFAR flux as well as redshift of the sources, and compared these to literature.
ContributorsStawinski, Stephanie Mae (Author) / Scannapieco, Evan (Thesis director) / Windhorst, Rogier (Committee member) / Karen, Olsen (Committee member) / Department of Physics (Contributor) / School of International Letters and Cultures (Contributor) / School of Earth and Space Exploration (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
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Description
I test the hypothesis that galactic magnetic fields originate from regions of dense
star formation (Dahlem et al. 2006) by comparing maps of 120-240 MHz synchrotron emission and hydrogen alpha (Hα) emission of the tidally-interacting, edge-on, barred spiral galaxy UGC 9665. Synchrotron emission traces magnetic field strength to a rough first

I test the hypothesis that galactic magnetic fields originate from regions of dense
star formation (Dahlem et al. 2006) by comparing maps of 120-240 MHz synchrotron emission and hydrogen alpha (Hα) emission of the tidally-interacting, edge-on, barred spiral galaxy UGC 9665. Synchrotron emission traces magnetic field strength to a rough first order, while Hα emission traces recent massive star formation. UGC 9665 was selected because it was included in the LOw Frequency ARray (LOFAR) TwoMetre Sky Survey (LoTSS; Shimwell et al. (2017)) as well as the Calar Alto Legacy Integral Field Area Survey (CALIFA; Sanchez et al. (2012)). I generated vertical intensity profiles at several distances along the disk from the galactic center for synchrotron emission and Hα in order to measure how the intensity of each falls off with distance from the midplane. In addition to correlating the vertical profiles to see if there is a relationship between star formation and magnetic field strength, I fit the LOFAR vertical profiles to characteristic Gaussian and exponential functions given by Dumke et al. (1995). Fitting these equations have been shown to be good indicators of the main mode of cosmic ray transport, whether it is advection (exponential fit) or diffusion (Gaussian fit) (Heesen et al. 2016). Cosmic rays originate from supernova,
and core collapse supernovae occur in star forming regions, which also produce
advective winds, so I test the correlation between star-forming regions and advective regions as predicted by the Heesen et al. (2016) method. Similar studies should be conducted on different galaxies in the future in order to further test these hypotheses and how well LOFAR and CALIFA complement each other, which will be made possible by the full release of the LOFAR Two-Metre Sky Survey (LoTSS) (Shimwell et al. 2017).
ContributorsHuckabee, Gabriela R (Author) / Jansen, Rolf (Thesis director) / Windhorst, Rogier (Committee member) / Bowman, Judd (Committee member) / School of Earth and Space Exploration (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
Due to recent changes in climate, hurricanes have become more violent and destructive in the tropical region of the Caribbean. Extreme weather events have destroyed freshwater sources in many islands, affecting the overall food and water security of the region. More resilient forms of collecting freshwater for citizens and agriculture

Due to recent changes in climate, hurricanes have become more violent and destructive in the tropical region of the Caribbean. Extreme weather events have destroyed freshwater sources in many islands, affecting the overall food and water security of the region. More resilient forms of collecting freshwater for citizens and agriculture must be proposed in order to mitigate future weather impacts and increase future water security. Rainwater harvesting is an ideal and sustainable source of freshwater that can be adapted into existing households to help ease reliance on city water sources. Rainwater harvesting systems are effective sources of supplemental freshwater because they are easy to incorporate and inexpensive compared to other sources of freshwater. Dennis McClung, founder and owner of global charity, Garden Pool, has created the Climate Smart Farm, an agriculture system that incorporates rainwater harvesting to help create a more climate resilient farm. The Climate Smart Farm is adaptable and can be customized to incorporate solar energy, vertical gardening, aquaponics, hydroponics, plant propagation techniques, and more to grow crops in a more sustainable fashion. The system has recently been installed in the island of Barbuda, which was badly affected by the hurricanes in the summer of 2017. The system has been positively accepted by the country due to its ability to make agriculture simple and sustainable. It can be built with local materials, making the building process economy friendly. And with the addition of plant propagation techniques, the Climate Smart Farm can extend growing seasons and increase overall yields.
ContributorsLeung, Karyn Mae (Author) / Eakin, Hallie (Thesis director) / McClung, Dennis (Committee member) / School of Earth and Space Exploration (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
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Description
As we already know, fresh water is essential to human life as it sustains and replenishes our bodies. Water sustainability is clearly an important issue that need to be addressed in our world of growing demand and shrinking resources. The ASU Future H2O program seeks to make a difference in

As we already know, fresh water is essential to human life as it sustains and replenishes our bodies. Water sustainability is clearly an important issue that need to be addressed in our world of growing demand and shrinking resources. The ASU Future H2O program seeks to make a difference in the development of water sustainability programs by performing experiments that convert urine into reusable water. The goal is to make reusable water processes become inexpensive and easily accessible to local businesses. This promises a significant environmental impact. In order to make the process of development more efficient we can combine engineering technology with scientific experimentation. As an engineering student and an advocate of water sustainability, I have a chance to design the front-end platform that will use IoT to make the experimental process more accessible and effective. In this paper, I will document the entire process involved in the designing process and what I have learned.
ContributorsTran, Phung Thien (Author) / Boscovic, Dragan (Thesis director) / Boyer, Treavor (Committee member) / School of Earth and Space Exploration (Contributor) / Computer Science and Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
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Description
The goal of this thesis is to extend the astrophysical jet model created by Dr.
Gardner and Dr. Jones to model the surface brightness of astrophysical jets. We attempt to accomplish this goal by modeling the astrophysical jet HH30 in the spectral emission lines [SII] 6716Å, [OI] 6300Å, and [NII] 6583Å.

The goal of this thesis is to extend the astrophysical jet model created by Dr.
Gardner and Dr. Jones to model the surface brightness of astrophysical jets. We attempt to accomplish this goal by modeling the astrophysical jet HH30 in the spectral emission lines [SII] 6716Å, [OI] 6300Å, and [NII] 6583Å. In order to do so, we used the jet model to simulate the temperature and density of the jet to match observational data by Hartigan and Morse (2007). From these results, we derived the emissivities in these emission lines using Cloudy by Ferland et al. (2013). Then we used the emissivities to determine the surface brightness of the jet in these lines. We found that the simulated surface brightness agreed with the observational surface brightness and we conclude that the model could successfully be extended to model the surface brightness of a jet.
ContributorsVargas, Perry Bialek (Author) / Gardner, Carl (Thesis director) / Scannapieco, Evan (Committee member) / School of Mathematical and Statistical Sciences (Contributor) / School of Earth and Space Exploration (Contributor) / Barrett, The Honors College (Contributor)
Created2016-12
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Description
Despite similar climate, ecosystem, and population size, the cities of Hermosillo, Mexico and Mesa, USA manage their water very differently. Mesa has a stable and resilient system organized around state and federal regulations. Hermosillo, after rapidly industrializing, has not been able to cope with climate change and long-term drought conditions.

Despite similar climate, ecosystem, and population size, the cities of Hermosillo, Mexico and Mesa, USA manage their water very differently. Mesa has a stable and resilient system organized around state and federal regulations. Hermosillo, after rapidly industrializing, has not been able to cope with climate change and long-term drought conditions. Water distribution statistics, stakeholders, policy structure, and government organization were combined in an organizational framework to compare the practices of the two cities. These inputs were weighed against the outcomes and the sustainability of each system. While Mesa is part of a massive metropolitan area, Hermosillo is still developing into a metropolitan center and does not have access to the same infrastructure and resources. In Hermosillo local needs are frequently discounted in favor of broad political goals.
ContributorsMoe, Rud Lamb (Author) / Chhetri, Netra (Thesis director) / White, Dave (Committee member) / Robles-Morua, Agustin (Committee member) / Barrett, The Honors College (Contributor) / School of Earth and Space Exploration (Contributor) / School of Sustainability (Contributor) / School of Geographical Sciences and Urban Planning (Contributor)
Created2013-05
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Description

Over the last few decades, sustainability has become a great focus for individuals as well as businesses globally. The focus of this study was to understand why businesses purchase certain office supplies and why they may not be choosing to purchase the most sustainable options. The research question asked, “why

Over the last few decades, sustainability has become a great focus for individuals as well as businesses globally. The focus of this study was to understand why businesses purchase certain office supplies and why they may not be choosing to purchase the most sustainable options. The research question asked, “why are certain businesses reluctant to make positive, sustainable changes to their usage of office materials in their workplace environments?” Most companies do not look for alternatives that would benefit the environment when purchasing products for their office space. The reasons behind this hesitancy to change was studied through current literature on the topic as well as interviews conducted with Office Managers of several different businesses. Comparisons were made between each businesses’ decision patterns in order to find the root cause or causes of why companies do not choose more sustainable options when purchasing products for their workspaces. The interviews revealed that cost and quality are the most important factors these businesses take into consideration when purchasing office supplies. While some companies have looked into alternative products for their supplies, they ultimately choose to still purchase the less sustainable option. This is because the less sustainable option is often cheaper, and the company knows what quality to expect for the item. Overall, all of the Office Managers who were interviewed acknowledged some sort of sustainable practice that their company was taking part in, even if it did not directly relate to the types of office supplies that they purchase. This inclusion of general sustainable practices demonstrates how businesses are making efforts one way or another towards a more sustainable future. Therefore, this awareness to sustainability suggests that most, if not all businesses will eventually end up purchasing sustainable alternatives for their office supplies. However, the timeframe for which this occurs for each company will likely vary.

ContributorsOberlander, Rachel Lynn (Author) / Kappes, Janelle (Thesis director) / Augustin-Behravesh, Shirley-Ann (Committee member) / Dean, W.P. Carey School of Business (Contributor) / School of Earth and Space Exploration (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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Description

Stellar mass loss has a high impact on the overall evolution of a star. The amount<br/>of mass lost during a star’s lifetime dictates which remnant will be left behind and how<br/>the circumstellar environment will be affected. Several rates of mass loss have been<br/>proposed for use in stellar evolution codes, yielding

Stellar mass loss has a high impact on the overall evolution of a star. The amount<br/>of mass lost during a star’s lifetime dictates which remnant will be left behind and how<br/>the circumstellar environment will be affected. Several rates of mass loss have been<br/>proposed for use in stellar evolution codes, yielding discrepant results from codes using<br/>different rates. In this paper, I compare the effect of varying the mass loss rate in the<br/>stellar evolution code TYCHO on the initial-final mass relation. I computed four sets of<br/>models with varying mass loss rates and metallicities. Due to a large number of models<br/>reaching the luminous blue variable stage, only the two lower metallicity groups were<br/>considered. Their mass loss was analyzed using Python. Luminosity, temperature, and<br/>radius were also compared. The initial-final mass relation plots showed that in the 1/10<br/>solar metallicity case, reducing the mass loss rate tended to increase the dependence of final mass on initial mass. The limited nature of these results implies a need for further study into the effects of using different mass loss rates in the code TYCHO.

ContributorsAuchterlonie, Lauren (Author) / Young, Patrick (Thesis director) / Shkolnik, Evgenya (Committee member) / Starrfield, Sumner (Committee member) / School of Earth and Space Exploration (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
Description
Gamma-ray bursts (GRBs) are a type of astrophysical transient resulting from the most energetic explosions known in the universe. The explosions occur in distant galaxies, and their bright initial emission may only last a few seconds. Colibri is a telescope being built at the San Pedro Martir

Gamma-ray bursts (GRBs) are a type of astrophysical transient resulting from the most energetic explosions known in the universe. The explosions occur in distant galaxies, and their bright initial emission may only last a few seconds. Colibri is a telescope being built at the San Pedro Martir Observatory in Baja, CA, MX with high sensitivity in order to study these events at a high redshift. Due to how quickly GRBs occur, it is essential to develop an image reduction pipeline that can quickly and accurately detect these events. Using existing image reduction software from Coatli, which was programmed and optimized for speed using python, numerous time trials were performed in order to determine if the pipeline meets the time requirements with various factors being adjusted. The goal of this experiment is for the telescope to respond to, capture, and reduce the images in under 3 minutes. It was determined that the reduction was optimized when the number of files to be reduced was set equal to 16 or higher by changing the batch number and the blank sky subtraction function was performed. As for the number of exposures, one can take up to four 30 second exposures or twenty 5 second exposures and reduce them in under 3 minutes.
ContributorsHeiligenstein, Wren (Author) / Butler, Nathaniel (Thesis director) / Jansen, Rolf (Committee member) / Dimitrova, Tzvetelina (Committee member) / Barrett, The Honors College (Contributor) / School of Earth and Space Exploration (Contributor)
Created2024-05