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As part of the McDonald Observatory M dwarf planet search program, we present the results and detection limits for our high-precision radial velocity survey of 99 M dwarf stars. We also detail our efforts to improve the precision of our RV measurements as well as our frequency analysis methods. For any RV program, it is essential to obtain as high a precision as possible; increasing sensitivity can realistically reveal terrestrial-mass planets with our data. M dwarfs provide a unique opportunity to study these lower-mass planets (the so-called "super-Earths") from ground-based facilities; such planets are mostly undetectable around FGK stars, whose larger masses result in much smaller RV amplitudes. However, the low intrinsic luminosities of the M spectral type make it difficult to obtain high S/N measurements for a statistically significant sample, making our analysis improvements especially critical. Finally, we conduct a statistical analysis of the 21 known M dwarf planets. In particular, we use the photometric metallicity calibration for M dwarfs described in Johnson and Apps (2009) to further explore the frequency of planetary systems as a function of stellar metallicity. Our analysis confirms the correlation between stellar mass and the presence of giant planets, but also reveals a significant metallicity dependence on the presence of high-mass planets for M dwarfs. We show that the metallicities of our target sample are evenly distributed around solar [M/H], eliminating the possibility that the results of our survey will be biased due to metallicity effects. The frequency and characteristics of planets around M stars provides important insight into planet formation theories, especially for giant planets, which appear to form less easily around low-mass primaries. While previous results suggesting a dearth of short-period Jovian planets around M stars still holds, there is now a long enough observational time baseline to begin to characterize the frequency of planets with lower masses and larger orbital separations around these stars as opposed to other main sequence stars. / text

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2 pp. / Until the introduction of semi-dwarf wheat in the late 1960s, wheat varieties were typically one and a half to two times their current height. Most heirloom, traditional, or landrace varieties are considered standard-height wheat (e.g. Sonoran white); in general they are adapted to lower-input conditions, and cannot tolerate high-fertility environments without lodging. Lodging reduces grain yield, delays harvest, and increases harvesting costs. Standard-height wheat needs to be grown at a lower plant density and with less nitrogen and irrigation water than semi-dwarfs in order to prevent lodging, optimize yield, and make the most efficient use of resources.

Extensive photometric and spectroscopic observations have been obtained for the binary HS1136+6646, a newly formed post-common envelope binary system containing a hot ~DAO.5 primary and a highly irradiated secondary. H1136+6646 is the most extreme example yet of a class of short period systems containing a hot H-rich white dwarf with a K-M companion. An orbital period of 0.83607(3) days has been determined through the phasing of radial velocities, emission line equivalent widths, and photometric measurements spanning a range of 24 months. Radial velocity measurements yield an amplitude of K_WD = 69(2) km s^-1 for the white dwarf and K_K7V = 115 +/- 1 km s^-1 for the secondary star. Photometric measurements revealed a low amplitude modulation with a period of 234 minutes, associated with the rotation of the white dwarf. The white dwarf is estimated to have an effective temperature and gravity of ~100,000 K and log g~8.29 respectively, indicating the binary system is the second earliest post-CE objects known, having an age around 6.4x10^5 years. Indications are that the secondary star is overly luminous for its mass.I also present FUSE observations of the magnetic cataclysmic variable V405 Aurigae. Together with four other DQ Her type binaries, V405 Aur forms a small subclass of intermediate polars which are likely to evolve into low magnetic field strength polars. The FUSE spectrum exhibits broad O VI and C III emission-lines as well as a narrow O VI emission-line component which likely forms near the white dwarf surface in an optically thin gas. Radial velocity measurements restrict any orbital modulation to a very low amplitude (K_WD = 2.5(0.5) km s^-1) indicating that the binary system is at low inclination.Recent photometric and spectroscopic observations have revealed J0644+3344 to be a bright, deeply eclipsing cataclysmic variable binary with a 6.46488(24) hour period. Although the nature of the hot component is not presently clear, J0644+3344 is one of the brightest eclipsing nova-like cataclysmic variable system yet. As such, the possibility exists for an unambiguous determination of the masses and temperatures of both components in future studies.

Lake Winnipeg has the second largest walleye fishery in North America. The North and South Basins of the lake differ in many ways, e.g. water temperature, turbidity, and fish community. The study objectives were to determine if (a) growth, condition or diet of walleye, sauger or dwarf walleye differed between basins, (b) among seasons, and (c) whether the invasive rainbow smelt are associated with these differences. Walleye, sauger and dwarf walleye were caught using gill-nets and analysed for growth, condition and diet in all seasons. Walleye and sauger in the North Basin showed higher growth rates and condition than in the South Basin. Diet in the South Basin had more diverse species composition, whereas in the North Basin, the diet consisted almost entirely of rainbow smelt. Some seasonal variation was also documented and the impact of rainbow smelt seems to be positive for these piscivorous fish in Lake Winnipeg.

Study determined if 2MASS photometric data are reliable for luminosity classification using JHK plots of Reid and Hawley (2001). Effects of interstellar reddening on the placement of giant and dwarf data on the JIIK plot were analyzed. Dwarfs (N=54) were selected from Hipparchos and the 2MASS data reduced to an H-K range of 0.14-0.40. A disk dwarf region was identified using linear regression on the low space velocity stars. Giants selected from Volume 5 of the Michigan Catalogue of HD stars and SAG stars classified at Ball State University. They yielded 304 individual giants and 13 matches in the 0.14-0.40 H-K range respectively. The 2MASS data was reliable for luminosity classification of the SAGBSU giants. The classification of the Michigan giants was not possible due to interstellar reddening and the likely presence of faint giant companions. / Department of Physics and Astronomy

This paper presents the photometric luminosity classification of M dwarfs in Kaptyn’s Selected Area 124 (SA124). This project is part of an ongoing program at Ball State University to use R, I, and CaH photometry in an attempt to probe low luminosity star contributions to the luminosity function. Data is taken at the Southeastern Association for Research in Astronomy (SARA) telescope located at Kitt Peak, Arizona. With a limiting magnitude of R=15.0, we have observed ~75% of a full square degree in SA124 and have detected 19 M dwarf candidates, which are then confirmed using matched 2MASS J, H, and K magnitudes. We present the detections of 19 ±4.4 M dwarfs observed in SA124. The current estimates of our luminosity function are consistent with those previously determined for the galactic plane. / Department of Physics and Astronomy

This investigation in the 24 Kapteyn Selected Areas along the celestial equator examined 21 red dwarf stars identified in an objective-prism survey. These stars were classified as red dwarf stars using light at wavelengths between 5800 A and 6800 A. Using calcium-hydride-based luminosity classification, this study found 13 of these stars to be red giant stars, and only 6 stars were found to be red dwarfs. One star was determined to be warm star. One star was not clearly distinguishable as a dwarf or giant. Distance calculations for the red dwarf stars found that these stars lie within 40 parsecs of the sun. / Department of Physics and Astronomy