SX Phoenicis Stars Suzanne Shuda Faculty Advisor: Dr

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SX Phoenicis Stars Suzanne Shuda Faculty Advisor: Dr. Oluseyi, Dept of Physics and Space Sciences, Florida Institute of Technology Introduction Methods and Design Results SX Phoenicis stars are usually found in I crossmatched the SDSS and SIMBAD A total of 42 SX Phoenicis stars were the outer regions of the galaxy which is databases to compile a list of likely SX found with metallicity measurements, called galactic halo. Their luminosity Phoenicis stars. I used SQL queries to much more than the previously known varies with a period of 1-2 hours. They display the information I wanted. I used 13 SX Phe stars. An O-C diagram are interesting because they are very old known characteristics such as spectral describes the observed minus but have not become white dwarfs as type and period to narrow down the stars calculated luminosity of a specific star. expected. Fewer than 20 field SX in the database. I learned the best queries The purpose is to study the long term Phoenicis stars are known to exist. By by experimenting with the suggestions in changes in luminosity. CY Aquarii, one studying these stars, we can learn about the tutorials on the website for SDSS. of the more well-known SX Phe stars how they formed, the makeup of the Using the data list from the SDSS which has been studied in the past. An galactic halo, and possibly locate dwarf Database, I crossmatched the list with the O-C diagram for CY Aquarii is shown in galaxies. The origin of SX Phe stars is SIMBAD database using the internal Fig 2. still unknown. function in SIMBAD. I also found the Conclusions/ Future Work metallicity of the stars in the databases. Fig 1: H-R diagram relates surface temperature The results show that there are very The metallicity or [Fe/H] is a measure of with luminosity. SX Phoenicis stars are located few SX Phoenicis stars in the galaxy the density of heavy elements within a in the instability strip, close to the main and very little data from them. By sequence. star. The metallicity can then be used to studying the metallicities, the origin of determine whether or not the star has these stars can be determined. If gone through s-process element there is a high metallicity, the star has enrichment and therefore determine the gone through s-process element origin of the star. enrichment and was most likely Fig 2: O-C formed by stellar cannibalism. If not, it diagram of CY was most likely formed through stellar Aquarii. Shows collisions. The methods used for this long-term experiment can be applied to any changes in the period other type of variable star. Other uses would be determining the overall metallicity of the galactic halo. .

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Arxiv:1710.00185V1
Accepted for publication in the Publications of the Astronomical Society of the Pacific, 21 July 2017 Preprint typeset using LATEX style emulateapj v. 05/12/14 PROJECT SOLARIS – A GLOBAL NETWORK OF AUTONOMOUS OBSERVATORIES – DESIGN, COMMISSIONING AND FIRST SCIENCE RESULTS S.K. Koz lowski1,2, P.W. Sybilski1,3, M. Konacki1,2,3, R.K. Paw laszek1,3, M. Ratajczak 4, K.G. He lminiak1 and M. Litwicki1,2 Accepted for publication in the Publications of the Astronomical Society of the Pacific, 21 July 2017 ABSTRACT We present the design and commissioning of Project Solaris, a global network of autonomous observatories. Solaris is a Polish scientific undertaking aimed at the detection and characterization of circumbinary exoplanets and eclipsing binary stars. To accomplish this task, a network of four fully autonomous observatories has beed deployed in the Southern Hemisphere: Solaris-1 and Solaris-2 in the South African Astronomical Observatory in South Africa, Solaris-3 in Siding Spring Observatory in Australia and Solaris-4 in Complejo Astronomico El Leoncito in Argentina. The four stations are nearly identical and are equipped with 0.5-m Ritchey-Crétien (f/15) or Cassegrain (f/9, Solaris-3) optics and high-grade 2K x 2K CCD cameras with Johnson and Sloan filter sets. We present the design and implementation of low-level security, data logging and notification systems, weather monitoring components, all-sky vision system, surveillance system and distributed temperature and humidity sensors. We describe dedicated grounding and lighting protection system design and robust fiber data transfer interfaces in electrically demanding conditions. We discuss the outcomes of our design as well as the resulting software engineering requirements.
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