COE Observatory Report 2005-2006

Tennessee State University
Center of Excellence in Information Systems
Nashville, Tennessee 37209

This report covers the interval October 1, 2005 through September 30, 2006.

The astrophysics program in the TSU Center of Excellence concentrates on photometry and spectroscopy of cool giants, chromospherically active stars, solar-type stars, planetary-candidate host stars, binary and multiple stars, and pulsating variables, as well as building and managing robotic telescopes and applying automation to astronomy. Astronomy staff in 2005-06 were Geoffrey S. Burks, Michael R. Busby, Joel A. Eaton, Francis C. Fekel, Gregory W. Henry, and Michael H. Williamson. Student research assistants were Sharina Haynes and Daniel Henry.

During this time period, the Center of Excellence was temporarily located in Holland Hall on TSU's main campus; it will move to permanent offices in the yet unnamed Research Building in spring, 2007.


Center of Excellence astronomers operate several automatic telescopes at Fairborn Observatory in the Patagonia mountains of southern Arizona. Fairborn is a non-profit Educational Corporation directed by Lou Boyd and dedicated to the advancement of automated astronomy. Operational TSU telescopes include the T2 0.25 m automatic photoelectric telescope (APT) for Johnson VRI photometry, the T3 0.40 m APT for Johnson BV photometry, the T4 0.75 m APT for Stromgren by photometry, the T8, T10, T11, and T12 0.80 m APTs, also for Stromgren by photometry, and the T13 2.0 m automatic spectroscopic telescope (AST) for high-resolution echelle spectroscopy.

During the most recent observing year (2005 September - 2006 July), the T2 0.25 m APT collected 4468 group observations during 238 nights, mostly of the unusual Be variable star gamma Cas. In 18 years of operation, the T2 APT has collected 115,040 group observations of variable stars. The T3 0.40 m APT collected 18,555 group observations, primarily of chromospherically active single and binary stars and gamma Doradus candidates, on 241 nights. In its 19 years of operation, it has collected 264,511 group observations. The T4 0.75 m APT acquired 7,298 group observations of solar-type stars on 238 nights. It has collected a total of 84,645 group observations in 14 years of operation. The T8 0.80 m APT made 10,388 group observations of solar-type stars on 233 nights. In 11 years of operation, it has collected a total of 82,295 group observations. The T10 0.80 m APT made a total of 10,877 group observations of solar-type stars on 242 nights. In 6 years of operation, it has collected a total of 57,902 group observations. The T11 0.80 m APT made a total of 10,948 group observations of solar-type stars on 242 nights. In 6 years of operation, it has collected a total of 56,054 group observations. The T12 0.80 m APT made a total of 12,736 group observations of planetary candidate stars on 237 nights. In its 6 years of operation, it has collected a total of 61,763 group observations. Finally, the T13 2.0 m AST collected 7229 high-dispersion echelle spectra on 262 nights; it has acquired a total of 27,612 spectra in its first 3 full years of operation. Further information about the APTs and the AST can be found on the Web at and, respectively.

Henry (along with CoI's P. Butler and M. Lopez-Morales (Carnegie Instituion of Washington) marked the first year of their National Science Foundation (NSF) Major Research Instrumention (MRI) grant to construct three new 0.8 m APTs to expand the Center's planetary search program. Fairborn Observatory was awarded the contract to build the three telescopes. Two of the three APTs will be installed at Carnegie's Las Campanas Observatory in Chile while the third APT will remain at Fairborn. Construction of the major mechanical and optical components of the telescopes is underway. Boyd has gathered most of the additional components needed to assemble the complete automated systems when the telescope mounts and optics are finished. A site has been selected at Las Campanas and constuction of the automated enclosure for the two southern APTs will take place in 2007.

Eaton (with CoI's Henry and J. Hall and G. W. Lockwood of Lowell Observatory) got a grant from the NSF Major Research Instrumention program for building a dedicated Ca II H&K spectrograph to observe the solar-type stars Henry is monitoring with the APTs. The Mt. Wilson/Lowell H-K program will effectively move to the TSU Automatic Spectroscopic Telescope and become its primary program within 2-3 years. The project to build this new instrument began in August 2006.

TSU and Vanderbilt astronomers have collaborated to place a new 0.36 m telescope for automated imaging on the roof of Vanderbilt's Dyer Observatory. The telescope (referred to as the Dyer-14 or D14) was funded by a NASA New Technology grant from Marshall Space Flight Center. It consists of a Celestron C-14 f/11 optical tube assembly, an Astro-Physics GTO 1200 telescope mount, an Optec TCF-S focuser, and an SBIG ST-1001E CCD camera with 1024x1024 24-micron pixels. The resulting field of view is 21 x 21 arcminutes at 1.26 arcseconds per pixel. Dyer Observatory superintendent R. Alvey designed and built an enclosure to house the telescope. Williamson at TSU developed the necessary hardware and software (in C under Linux) to automate the enclosure and control the mount, CCD camera, and focuser. The program also uses a Polaris camera and a rain sensor to determine when it is safe to begin observing. Automated imaging operations began in September; TSU and Vanderbilt astronomers and students are sharing observing time on the telescope. Williamson will develop the necessary reduction software in the coming months.



Eaton has used an empirical model for the chromosphere/wind of 31 Cygni to predict what the K supergiant component would look like as a single star for a wide range of diagnostics. The precious few emission lines actually excited in the chromospheres/winds of such binary components seem to have about the same intensities as those lines in single stars. The main innovation of this work was using the pressure distribution required to drive the observed wind to predict just how much the wind is clumped at each level (of the order of 3-10X). This model predicts the intensities seen in single stars to within a factor of two for the critical UV lines and the radio continuum. It also casts doubt on the interpretation of C II] as a measurement of global electron density and explores the kinematics of the emitting gas as measured from line widths and shapes in the ultraviolet.

Eaton finished a paper with Felecia G. Shaw (undergraduate student) about the zeta Aurigae binary 22 Vul. This system is noteworthy in that it contains a G supergiant instead of the cooler, larger K supergiants found in the classical zeta Aur stars. Eaton & Shaw used spectra from NSO and the TSU spectroscopic telescope to refine the orbit somewhat (not especially important) and the spectroscopy and photometry from an APT to discuss the mass ratio and properties of the two stars (somewhat more interesting). They analyzed archival IUE spectra to obtain physical conditions in the chromosphere and wind of the G supergiant, in particular, excitation temperatures for a wide range of heights (useful for testing ideas about chromospheric structure). The potentially most interesting result is that the G star and its chromosphere are rotating non-synchronously, as E. Griffin et al. found from optical data, and that the chromosphere/wind seems to be rotating as a solid body to several stellar radii in the archival IUE spectra.

Binary and Multiple Stars

Eaton and Henry have analyzed extensive spectroscopy and photometry for the eclipsing RS CVn star SZ Piscium. Their contemporaneous data for 1993-94 show that spots and active regions on the cool chromospherically-active component were visible all the time. Subsequent photometry seems to show this is the usual condition for the star. The spots in 1993-94 were probably no bigger than 8-10 deg angular radius. Eaton and Henry derive a better light-curve solution in which the active K subgiant is still rather close to its Roche lobe. The extensive new radial velocities from the TSU AST show SZ Psc is a triple system (most likely with an 1143-day period), and Eaton and Henry probably detected this faint third star in its Na D lines. H-alpha strengths covering about two years showed only weak phase dependence, not unexpectedly for a star with spots likely always visible, but with some humongous multi-orbit "flaring". The resulting paper discusses the meaning of the "filling in" of H-alpha as an ambiguity of local and global phenomena.

Fekel, in collaboration with C. Scarfe (Univ. of Victoria) and others, is continuing spectroscopic observation of about 20 close multiple systems and a half dozen speckle binaries to obtain fundamental parameters. For most of the systems speckle observations have been obtained by the CHARA group (Georgia State Univ.) and USNO observers. As part of this program Fekel and Henry along with D. Barlow (Univ. of Victoria) and D. Pourbaix (Univ. Libre de Bruxelles) analyzed 20 years of spectroscopic observations of the multiple star HD 131861. Lines of two of three components, an F5 V primary in a short-period orbit and a G8 V secondary, have been detected. The inner orbit is circular with a period of 3.5507439 days, while the outer orbit of the system has a period of 1642 days (4.496 yr) and a relatively low eccentricity of 0.10. Analysis of the Hipparcos data produces a well-determined astrometric orbit for the long-period system with an inclination of 52 degrees. Our photometric observations show shallow primary and secondary eclipses of the short-period pair, and eclipse solutions result in an inclination of 81 degrees. Thus, the long- and short-period orbits are not coplanar. The mass of the unseen third component is 0.7 solar masses, corresponding to a mid-K dwarf. The total mass of the system, 3.08 solar masses, leads to a semimajor axis of 4 AU for the outer orbit. The F5 V primary is rotating more slowly than it would if it were synchronously rotating, while the G8 V secondary may be synchronously rotating. The lithium abundance of the F5 V primary is similar to the initial lithium abundance found for Population I dwarfs and so indicates no significant dilution.

Fekel and J. Tomkin (Univ. of Texas) are obtaining spectra of about 40 known spectroscopic binaries with orbital periods greater than 5 days. Such stars are likely targets of various optical interferometers that are now in operation. The three-dimensional orbits resulting from the combination of accurate new spectrographic orbits with astrometric orbits from the interferometers will give precise masses, parallaxes, and the evolutionary status of the components of these systems. The first paper from this project, discussing spectroscopic orbits of 3 of the stars (RR Lyn, 12 Boo, and HR 6169), was published recently in the Astronomical Journal. In addition, Fekel gave a progress report on the project at IAU Symposium 240. Fekel and Tomkin have detected secondaries for 10 previously single-lined binaries in this group, turning them into vastly more useful double-lined systems. Some of the top priority systems are now being observed with the CHARA interferometric array. An example of recent progress in this project is HD 205539, which Fekel and Tomkin are analyzing in collaboration with A. Boden (Cal. Tech.) and W. Torres (CfA). They have interferometric observations from the Palomar Testbed Interferometer in hand and have nearly finished making the spectroscopic observations.

In other analyses of spectroscopic binaries, Fekel and Williamson, collaborating with TSU students C. Buggs, G. Onuoha, and B. Smith, have analyzed the binary star HR 1613. From two sets of radial velocities, one from KPNO and one from the 2 m TSU AST, they obtained orbital elements. This single-lined binary has an orbital period of 8.11128 days and a nearly circular orbit. The primary has an A9 V spectral type and a vsini of 11 km/sec, while the unseen secondary is likely a K or M dwarf. Spectral classifications and spectrum synthesis analysis indicate that the abundances of the primary are normal. The possibility that the primary of HR 1613 is seen nearly pole-on is rejected, and instead Fekel et al. argue that its rotational inclination is at least 20 degrees, resulting in an equatorial rotational velocity of 30 km/sec or less. Slowly rotating A stars almost always have spectrum peculiarities, being classified as either Ap or Am stars, but HR 1613, with its essentially solar abundances, appears to be a major exception.

Also from 2 m TSU AST data, Fekel, Williamson, and D. Pourbaix are computing new spectroscopic and astrometric orbits for HR 672 (G0.5 IV+?). A search for spectral lines of the secondary was unsuccessful, but because an astrometric orbit can be determined from the Hipparcos data, much information about the two components of this binary can be determined.

Fekel, in collaboration with K. Hinkle (NOAO), R. Joyce (NOAO) and P. Wood (Australian National Univ.), has continued a program of high-resolution infrared spectroscopy to obtain orbital elements of over 50 southern symbiotic binaries. This survey will greatly supplement recent results for 15 systems observed in a northern hemisphere program. Out of nearly 200 known symbiotics, there currently are only about 30 systems with well-determined orbital elements. Thus, the results from this observing program will provide statistics on a greatly expanded sample of symbiotic binaries. To date, the observations indicate that the vast majority of southern symbiotics have orbital periods of at least 500 days. The destruction of Mt. Stromlo Observatory in 2003 has greatly slowed the project because no suitable southern telescope has been found to continue this extensive long-term program. As a partial remedy, the group are observing those southern symbiotic stars north of -40 degrees declination at 1.01 microns with the coude feed telescope at Kitt Peak National Observatory and have obtained a few additional infrared spectra with Gemini South in Chile.

As a first step in the symbiotics project, Fekel, Hinkle, Joyce, Wood, and T. Lebzelter (Univ. of Vienna) finished orbits for three southern S-type systems with M-giant components. Of the three, Hen 2-173 has the longest orbital period, 911 days, and the least circular orbit, eccentricity = 0.21. Its large mass function suggests that Hen 2-173 may even be an eclipsing system. For CL Sco the spectroscopic orbital period of 626 days is identical to the previously determined photometric period (625 days). AS 270 has a similar orbital period, 671 days, while both CL Sco and AS 270 have circular orbits. Of these stars, only CL Sco has been extensively investigated previously, so the authors placed their results in context by invoking the extensive compilations of properties of symbiotic systems by Kenyon & Webbink. These stars agreed with a period-eccentricity relation for 30 S-type symbiotics: Eighty-one percent of the S-type systems with orbital periods up to 800 days have circular orbits, while only 22% with periods greater than 800 days do. This distribution is quite unlike that for G and K giants; rather, it is similar to that for barium stars, another type of mass-transfer binary, which also consists of a late-type giant and a white dwarf companion.

Henry, Fekel, J. Sowell (Georgia Tech), and J. Gearhart (Georgia Tech) have obtained and analyzed photometry and spectroscopy of HD 71636, a detached eclipsing binary with a period of 5.013 days consisting of two F-type stars on the main sequence.

Chromospherically Active Stars

Active cool stars continue to be of interest in the automated astronomy program. Henry collaborated with K. Biazzo and A. Frasca (Catania Astrophysical Observatory) and others to compare photometry from the T4 APT with contemporaneous spectroscopy of the young, active dwarfs kappa 1 Cet (G5 V) and chi 1 Ori (G0 V) acquired in 2000 and 2001. For kappa 1 Cet, a clear correlation between brightness and disk-integrated temperature and a clear anti-correlation betweeen brightness and equivalent width of H-alpha were observed, implying a spacial association between photospheric spots and chromospheric plages. For chi 1 Ori, there was little, if any, rotational modulation in any of the activity indicators, suggesting that the star was in a low state of activity and/or the distribution of activity was approximately uniform over stellar longitude. A paper detailing these results was submitted to the Astrophysical journal.

Henry and S. Berdyugina (Institute of Astronomy, Zurich) submitted a paper to the Astrophysical Journal Letters detailing their analysis of over 30 years of photometry of V711 Tauri = HR 1099. They confirmed the presence of cycles in mean brightness (~16 years) and peak-to-peak amplitude (~5 years) that were suggested over a decade ago. The 16 year cycle is related to variations of the total spot area, while the 5 year cycle is related to the distribution of spot area around the star. A first attempt is made to construct a stellar butterfly diagram by combining spot locations on the star determined with an inversion technique with a diffeential rotation law derived from a long series of Doppler Images.

Educational Outreach

Burks worked with student D. Henry on a Documentary about successful women astronomers. Much editing and organizational work was required. Burks also worked with student S. Haynes on a project headed by Caty Pilachowski (Indiana University) on abundances of red giant stars in selected globular clusters. Work with Haynes and Henry is expected to continue.

Extrasolar Planets

Henry is continuing to make photometric brightness measurements of planetary candidate host stars to search for additional planetary transits of bright stars and to confirm new planetary candidates, primarily in collaboration with the California and Carnegie planet-search group led by G. Marcy (Univ. of California) and P. Butler (Carnegie Institution of Washington). Major effort this year was spent on the N2K (Next 2000 Stars) Project. This project uses the Lick, Keck, Magellan, and Subaru telescopes to search for short-period gas giant planets around a new sample of 2000 F - M metal-rich main sequence and subgiant stars brighter than V = 10.5. The goal is to find new short-period planets that transit host stars bright enough to allow detailed follow up observations both from the ground and from space. New short-period planets were announced around the stars HD 33283, HD 86081, HD 109749, HD 149143, HD 189269, and HD 224693. The planetary orbital periods range from 2.14 to 26.73 days. All five stars are very metal rich compared to the Sun. Sadly, none of the planets were found to transit their host star, although transits of the planets with the longest periods (HD 33283b and HD 224693b) are not ruled out.

In addition to the discovery of these new short-period planets, Henry collaborated on the analyses of new radial velocity and photometric observations of three planetary systems previously known. New radial velocities of HD 149026 acquired during transit, along with existing radial velocity and photometric observations were used to model the Rossiter-McLaughlin effect, the shifting of photospheric line profiles that occurs when a planet occults a portion of the rotating stellar surface. The new model confirms and improves previously published orbital and planetary parameters, including the remarkably small planetary radius of 0.72 Rjup. The new data also allow for the determination of the angle between the apparent stellar equatorial and planetary orbital planes. Within the uncertainties, the two are coplanar, making a collisional origin of this very dense planet unlikely. A new multi-site photometric campaign was carried out on the three-planet system GJ 876 to look for transits of the 30 day (planet c) and 60 day (planet b) planets, which experience strong mutual perturbations. Transits of planet c do not currently occur, while transits of planet b were not entirely ruled out but are unlikely. (Transits of planet d, with a 1.93776 day orbit, have previously been shown not to occur). Finally, new radial velocity and photometric observations of HD 189733 enabled a Rossiter-McLaughlin analysis of the 2.219 day planet orbiting this star. As with HD 149026 discussed above, the angle between the sky projections of the stellar spin axis and orbit normal were found to be zero within the errors. This is the third case (including HD 209458) for which this angle has been measured and found to be small and consistent with zero, strongly suggesting that the inward migration of short-period planets generally preserves spin-orbit alignment.

Henry began a new collaboration with Jian Ge (University of Florida) and his exoplanet hunting team. Ge has developed a series of instruments that use a dispersed fixed-delay interferometer (DFDI) for high-precision, high-throughput radial velocity measurements. While multi-fiber capability is being developed and tested for an extensive survey, a proto-type single-fiber instrument (called the Exoplanet Tracker or ET) discovered periodic radial velocity variations in HD 102195 during testing at the KPNO coude-feed telescope. Radial velocities exhibited a semi-amplitude of 63 m/sec and a period of 4.11434 days. Photometric observations with the T10 APT at Fairborn found no significant brightness variability, demonstrating that the radial velocities were due to planetary-reflex motion. The photometry also ruled out the existence of transits. The results were published in the Astrophysical Journal.

Gamma Doradus Stars

Henry and Fekel are continuing their photometric and spectroscopic studies of candidate gamma Doradus stars primarily with the T3 APT and the KPNO coude feed telescope. Their spectroscopic and photometric work has proven the gamma Doradus nature of the majority of stars in this class.

Henry, Fekel, and S. Henry (Clemson Univ.) have completed another paper for the Astronomical Journal confirming 11 additional gamma Doradus variables. The candidates were chosen both from the lists of G. Handler (Univ. of Vienna) and from lists of variable comparison stars found with the various APTs. Including a couple new stars from the literature, the total number of confirmed gamma Doradus variables now stands at 66. All are dwarfs or subgiants and lie within a well-defined region of the H-R diagram that overlaps the cool edge of the Delta Scuti instability strip. HD 8801, discovered a couple years ago with one of the APTs, remains the only gamma Doradus star that also lies in the overlap region of the Delta Scuti strip and exhibits intrinsic pulsation modes of both types.

Henry, Fekel, and S. Henry are continuing work on their volume-limited survey of 275 gamma Doradus candidates. The 39 variables in the primary sample of 114 stars have all been reobserved at higher cadence with the T3 APT. Henry and S. Henry are analyzing those data to determine how many of the 39 variables are new gamma Doradus stars. The T3 APT will reobserve the 36 variables in the secondary sample of 161 stars at higher cadence over the next two years. Fekel continues to make spectroscopic observations of these stars to obtain radial velocities and other stellar properties. This study will provide the first measurement of the incidence of gamma Doradus variability and further refine the position of the gamma Doradus instability strip.

Solar-Type Stars

Henry continues his program of long-term study of photometric variations in a large sample of over 300 solar-type stars with the T3, T4, T8, T10, and T11 APTs. Photometric time series measurements now span 9 to 14 years. J. Hall and Lockwood continue to make new Ca II H & K measurements of a modest subsample of the 300 stars. Full H & K coverage of the APT sample of stars must await completion of the H & K spectrograph funded by NSF for the TSU 2.0 m AST.

Henry and S. Henry, along with Lockwood and Skiff (Lowell Observatory), and S. Baliunas, R. Donahue, and W. Soon (Center for Astrophysics) have completed a long-term study of 32 solar-type stars that were observed by the completed Lowell solar-type star program and continue to be observed by the APT program. The two separate time series measurements for each star were successfully meshed into combined light curves that span 13 - 20 years. Parallel chromospheric Ca II H & K emission data span the entire interval. The extended data strengthen the relationship between chromospheric and brightness variability derived previously from the Lowell program. On a year-to-year timescale, young active stars become fainter when their Ca II emission increases while older less active stars become brighter when their Ca II emission increases. The Sun's total irradiance variation still appears to be somewhat smaller than stars in our limited sample with similar mean chromospheric activity, but we now regard this discrepancy as probably due mainly to our limited stellar sample. The work is being submitted to the Astrophysical Journal Supplement Series.

Fekel and Henry made a search for Maunder Minimum states in a sample of solar-type stars. They have obained high-resolution spectroscopy and precise photometry of nearly 350 single, late-F to early-K dwarfs and some subgiants. These solar-type field stars range in age from about 200 million to 10 billion years. For the sample of stars they plot rotational velocity versus chromospheric activity in an attempt to identify stars in unusually low activity states. Stars with rotational velocities equal to or greater than 3 km/sec but with solar or less than solar chromospheric activity are chosen as possible candidates. After eliminating substantially evolved stars from consideration, the photometric variability of the remaining main sequence stars is examined. They find 7 stars in low activity states that may be similar to the Sun's Maunder minimum. However, a longer time span of photometric and Ca II H and K observations is needed to confirm the low activity in these candidates.


For 15 years Fekel has monitored the radial velocities of about 30 slowly rotating B and A stars, which are candidates for early-type velocity standards. A bootstrap procedure has been used to tie the velocities of the early-type stars to the IAU late-type velocity system. Most of the early- and mid-B type stars have variable velocities. However, about two-thirds of the slowly rotating late-B and A-type stars appear to have constant velocities. The 10 stars with the most constant velocities are HR 153, HR 675, HR 1389, HR 2010, HR 2489, HR 3383, HR 5447, HR 7512, HR 7773, and HR 8404.

Henry and collaborators M. Smith (Catholic University of America) and E. Vishniac (Johns Hopkins University) published a new study of the unusual classical Be star gamma Cas. They reported nine years of photometric monitoring with the T3 APT as well as simultaneous observations in 2004 November with the RXTE satellite. The observations disclosed no correlated optical response to the rapid X-ray flares in this star. Consistent with earlier studies, the optical light curves show that gamma Cas undergoes ~3% amplitude cycles with lengths of 50 - 91 days. Over the 9 days of monitoring the star with RXTE, the X-ray flux varied in phase with these optical cycles. In general, the amplitude of the V magnitude cycles are 30% - 40% larger than the corresponding B amplitude, suggesting that the production site of the cycles is circumstellar. The authors also discovered a coherent period of 1.21581(4) days present in all the data, which appears consistent only with rotation. The full amplitude of this variation is only 0.0060 mag in both filters, and, surprisingly, its waveform is almost sawtooth in shape. This variation is likely to originate on the star's surface in a complex magnetic field and a possible heterogeneous surface distribution of metals.

Eaton, relishing the role of Hebrew prophet, gave a talk at the semi-annual SPIE Telescopes Conference in Orlando, Florida, about how to streamline the traditionally bureaucratic task of managing instrument development in the university setting. He argued for a more informal management style than used in large-scale projects, one that identifies just what tasks are really necessary and ruthlessly eliminates overhead. He thereby discussed ways of achieving the goals of project management without getting bogged down in its formalities. Finally, he stressed the overweaning importance of getting the right people to work on a project, and identified two critical challenges in this environment: 1) keeping one's contractors on task and 2) dealing with the planned inefficiencies of the university's purchasing system.


Aarum Ulvas, V. & Henry, G. W. 2005, "Why Do Some Spotted Stars Become Bluer as They Become Fainter," in Proceedings of the 13th Cambridge Workshop on Cool Stars, Stellar Systems, and the Sun, eds. F. Favata, G. Hussain, & B. Battrick, ESA SP-560, p. 377

Biazzo, K., Frasca, A., Catalano, S., Marilli, E., Henry, G. W., & Tas, G. 2005, "Starspot Temperature Along the HR Diagram," MSAIS, 9, 220

Biazzo, K., Frasca, A., Henry, G. W., Catalano, S., & Marilli, E. 2005, "Photospheric Temperature Measurements in Young Main Sequence Stars," in Proceedings of the 13th Cambridge Workshop on Cool Stars, Stellar Systems, and the Sun, eds. F. Favata, G. Hussain, & B. Battrick, ESA SP-560, p. 445

Biazzo, K., Frasca, A., Marilli, E., Henry, G. W., Soydugan, F., Erdem, A., & Bakis, H. 2006, "First Simultaneous Photospheric and Spectroscopic Analysis of the Active Star IT Com," IBVS, No. 5740

Eaton, J. A. 2005, "Evolution, intelligent design both flawed but should be taught," editorial in The Tennessean, 22 Sept. 2005, p. 15A

Eaton, J. A. 2006, "Project Management at a University," in Modelling, Systems Engineering, and Project Management for Astronomy II, SPIE 6271, eds. M. J. Cullum & G. Z. Angeli (SPIE: Bellingham, WA), 627105

Fekel, F. C. & Henry, G. W. 2006, "Spectroscopy and Photometry of the Double-Lined Binary HD 149420," AJ, 131, 1724

Fekel, F. C., Henry, G. W., Barlow, D. J., & Pourbaix, D. 2006, "HD 131861, A Double-Lined Spectroscopic Triple System," AJ, 132, 1910

Fekel, F. C., Williamson, M., Buggs, C., Onuoha, G., & Smith, B. 2006, "HR 1613: A Slowly Rotating, A-Dwarf, Spectroscopic Binary with Solar Abundances," AJ, 132, 1490

Fischer, D. A., Laughlin, G., Marcy, G. W., Butler, R. P., Vogt, S. S., Johnson, J. A., Henry, G. W., McCarthy, C., Ammons, M., Robinson, S., Strader, J., Valenti, J. A., McCullough, P. R., Charbonneau, D., Haislip, J., Knutson, H. A., Reichart, D. E., McGee, P., Monard, B., Wright, J. T., Ida, S., Sato, B., & Minniti, D. 2006, "The N2K Consortium. III. Short-Period Planets Orbiting HD 149143 and HD 109749," ApJ, 637, 1094

Ge, J., van Eyken, J., Mahadevan, S., DeWitt, C., Cohen, R., Vanden Heuvel, A., Fleming, S., Guo, P., Kane, S., Henry, G. W., Israelian, G., & Martin, E. 2005, "The First Extrasolar Planet Discovered with A New Generation High Throughput Doppler Instrument," BAAS, 37, 1487

Ge, J., van Eyken, J., Mahadevan, S., DeWitt, C., Kane, S. R., Cohen, R., Vanden Heuvel, A., Fleming, S. W., Guo, P., Henry, G. W., Schneider, D. P., Ramsey, L. W., Wittenmyer, R. A., Endl, M., Cochran, W. D., Ford, E. B., Martin, E. L., Israelian, G., Valenti, J., & Montes, D. 2006, "The First Extrasolar Planet Discovered with a New Generation High Throughput Doppler Instrument," ApJ, 648, 683

Henry, G. W., Fekel, F. C., Sowell, J. R., & Gearhart, J. S. 2006, "HD 71636, A Newly Discovered Eclipsing Binary," AJ, 132, 2489

Hinkle, K. H., Fekel, F. C., Joyce, R. R., Wood, P. R., Smith, V. V., & Lebzelter, T. 2006, "Infrared Spectroscopy of Symbiotic Stars. IV. V2116 Ophiuchi = GX 1+4, The Neutron Star Symbiotic," ApJ, 641, 479

Johnson, J. A., Marcy, G. W., Fischer, D. A., Henry, G. W., Wright, J. T., Isaacson, H., & McCarthy, C. 2006, "An Eccentric Hot Jupiter Orbiting the Subgiant HD 185269," ApJ, 652, 1724

Johnson, J. A., Marcy, G. W., Fischer, D. A., Laughlin, G., Butler, R. P., Henry, G. W., Valenti, J. A., Ford, E. B., Vogt, S. S., Wright, J. T. 2006, "The N2K Consortium. VI. Doppler Shifts Without Templates and Three New Short-Period Planets," ApJ, 647, 600

Lebzelter, T., Wood, P., Hinkle, K., Joyce, R., & Fekel, F. 2005, "New Results on the Period-Luminosity Diagram of Long Period Variables," in Proceedings of the 13th Cambridge Workshop on Cool Stars, Stellar Systems, and the Sun, eds. F. Favata, G. Hussain, & B. Battrick, ESA SP-560, p. 747

Marsden, S. C., Berdyugina, S. V., Donati, J.-F., Eaton, J. A., Williamson, M. H., Ilyin, I., Fischer, D. A., Munoz, M., Isaacson, H., Ratner, M. I., Semel, M., Petit, P., & Carter, B. D. 2005, "A Sun in the Spectroscopic Binary IM Pegasi, the Guide Star for the Gravity Probe B Mission, ApJ, 634, L173

Mathias, P., Matar, E., Jankov, S., Chapellier, E., Le Contel, D., Le Contel, J.-M., Sareyan, J.-P., Valtier, J.-C., Fekel, F. C., & Henry, G. W. 2006, "Asteroseismology of Gamma Doradus Stars and the COROT Mission," MSAIS, 9, 470

Rivera, E. J., Lissauer, J. J., Butler, R. P., Marcy, G. W., Vogt, S. S., Fischer, D. A., Brown, T. M., Laughlin, G., Henry, G. W., "A ~7.5 Earth-Mass Planet Orbiting the Nearby Star, GJ 876," BAAS, 37, 1487

Shankland, P. D., Rivera, E. J., Laughlin, G., Blank, D. L., Price, A., Gary, B., Bissinger, R., Ringwald, F., White, G., Henry, G. W., McGee, P., Wolf, A. S., Carter, B., Lee, S., Biggs, J., Monard, B., & Ashley, M. C. B. 2006, "On the Search For Transits of the Planets Orbiting GL 876," ApJ, 653, 700

Smith, M. A. & Henry, G. W. 2005, "Rotational and Cyclical Variability in Gamma Cassiopeia," BAAS, 37, 1333

Smith, M. A., Henry, G. W., & Vishniac, E. 2006, "Rotational and Cyclical Variability in Gamma Cas," ApJ, 647, 1375

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