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The precision differential abundance (PDA) technique is applied to the mid-F stars Procyon and $\theta$ Scl using spectra from the ESO UVESPOP library. We relate PDA patterns to endogenous processes related to condensation or to exogenous processes connected to Galactic chemical evolution (GCE). We employ one-dimensional LTE models, but emphasize the use of weaker lines ($\leq$ 20 m\AA) than are typically used in such studies. We compare our results with PDAs of solar-type stars. Abundances and PDAs are determined for 28 elements: C, N, O, Na, Mg, Al, Si, S, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Y, Zr, Ba, La, Ce, Nd, Sm, Eu, and Gd. A plot of PDAs ($\theta$ Scl minus Procyon) vs. $Z$ shows a highly significant correlation. Moreover, local substructure of the plot for the elements Ca-Zn and neutron-addition elements is similar to that which can be found for solar twins. Our PDA vs. $Z$ plot structural similarity to plots that can be made from the extensive work of Bedell et al. (2018). That PDA structure and substructure is clearly a function of age., Comment: 8 pages, 4 figures. Accepted for publication in Astronomische Nachrichten

Bedell et al. (2018) give precision differential abundances for 79 mostly G-dwarf stars. We correct these abundances for Galactic chemical evolution in a manner similar to that used by these authors but with parameters derived from linear fits to plots of [El/H] vs. age in lieu of [El/Fe]. We examine the resulting abundances for correlations with the 50% condensation temperature using values from both Lodders (2003) and Wood et al. (2019), and compare with the results of Bedell et al. HD 196390 is distinct in having the most significant correlation of the 79-star sample. We report statistics for a subset of stars with lower significance, but of some interest., An updated and expanded version of a paper accepted by Research Notes of the AAS. Minor typos fixed

Traditional and statistical line-identification methods indicate the presence of Pm I and II, Tc I, and perhaps Tc II in the spectrum of the roAp star HD 101065. These methods also lead to the presence of Pm II and probably also Pm I in a related cool Ap star, HD 965. The spectroscopic evidence is strong enough that we would declare promethium to be present without hesitation, if any of its isotopes were stable. The longest-lived promethium isotope has a half-life of only 17.7 years. The presence of this element would mean that unrecognized processes - perhaps flare activities - are taking place in the atmospheres of these stars. The significance of such processes for galactic chemical evolution cannot be ruled out. We discuss the possibility that the highly improbable wavelength coincidences are due to chance, or due to contamination of the laboratory sources.

The review will cover the following topics: (1) Ionization energies; (2) Partition functions; (3) Sources of data for atomic and ionic wavelengths, transition probabilities, and broadening parameters, including nuclear effects (hfs and isotope shifts); (4) Opacities from photoionization of abundant elements (atoms and atomic ions) with emphasis on integration of TOPBASE material; and (5) Data bases for diatomic molecules. We emphasize topics of direct relevance to the synthesis of stellar spectra, primarily within the domain where LTE is useful. Additional parameters, such as line-broadening parameters, or excitation cross sections are not reviewed.

The abundance of holmium (Z = 67) in the Sun remains uncertain. The photospheric abundance, based on lines of Ho II, has been reported as +0.26 +/- 0.16 (on the usual scale where log(H) = 12.00), while the meteoretic value is +0.51 +/- 0.02. Cowan code calculations have been undertaken to improve the partition function for this ion by including important contributions from unobserved levels arising from the (4f^{11}6p + 4f^{10}(5d + 6s)^{2}) group. Based on 6994 computed energy levels, the partition function for Ho II is 67.41 for a temperature of 6000 K. This is approximately 1.5 times larger than the value derived from the 49 published levels. The new partition function alone leads to an increase in the solar abundance of Ho to log(Ho) = +0.43. This is within 0.08 dex of the meteoretic abundance. Support for this result has been obtained through LTE spectrum synthesis calculations of a previously unidentified weak line at 3416.38 A in the solar spectrum. Attributing the feature to Ho II, the observations may be fitted with log(Ho) = +0.53. This calculation assumes log(gf) = 0.25 and is uncertain by at least 0.1 dex.

A large reverberation mapping study of the Seyfert 1 galaxy NGC 7469 has yielded emission-line lags for Hbeta 4861 and He II 4686 and a central black hole mass measurement of about 10 million solar masses, consistent with previous measurements. A very low level of variability during the monitoring campaign precluded meeting our original goal of recovering velocity-delay maps from the data, but with the new Hbeta measurement, NGC 7469 is no longer an outlier in the relationship between the size of the Hbeta-emitting broad-line region and the AGN luminosity. It was necessary to detrend the continuum and Hbeta and He II 4686 line light curves and those from archival UV data for different time-series analysis methods to yield consistent results., Comment: 9 Pages, 7 figures, 6 tables. Accepted for publication in The Astrophysical Journal

Speckle observations are reported for 53 stars with composite spectra selected from the Michigan Spectral Catalogue in an effort to improve the orbits of known binaries and to discover new binaries among this class of objects. The data were obtained using the 1.3 and 2.4 m telescopes at the Michigan-Dartmouth-MIT Observatory and the Georgia Tech Research Institute speckle imaging system. For 50 stars in the sample for which no indication of duplicity was found in our data, we may place an upper limit of ≤02 on the separations at the epochs of observation. Three stars were resolved, including HD 26796, also discovered to be double by Hipparcos. A discussion of the accuracy of the measurements based on comparisons with speckle standard stars is presented.

We present the first spectroscopic verification of a bona fide chemically peculiar (CP) star in the Large Magellanic Cloud. CP stars reside on the upper main sequence and are characterized by strong global stellar magnetic fields with a predominant dipole component oriented at random with respect to the stellar rotation axis and displaced from the star's centre. Overabundances with respect to the Sun for heavy elements such as silicon, chromium, strontium and europium are also a common phenomenon. These objects are excellent astrophysical laboratories by which to investigate many of the processes connected with star formation and evolution. Several studies comparing the incidence of CP stars in the Large Magellanic Cloud with that of the Milky Way have been published. These investigations are based on the photometric detection of CP stars via the Δa system which has been tested and calibrated for objects in the Milky Way. From our spectroscopic observations made at Las Campanas Observatory, we are able to confirm one classical B8 Si star among the photometric sample, as well as one early B-type emission-line star which was also initially detected by its significantly deviating Δa value. We conclude that classical extragalactic CP stars do exist and that the photometric Δa system is able to detect them in an efficient way.

We have derived abundances for 54 elements in the extreme roAp star HD 101065. ESO spectra with a resolution of about 80 000, and S/N of 200 or more were employed. The adopted model has Teff=6600 K, and log(g)=4.2. Because of the increased line opacity and consequent low gas pressure, convection plays no significant role in the temperature structure. Lighter elemental abundances through the iron group scatter about standard abundance distribution (SAD) (solar) values. Iron and nickel are about one order of magnitude deficient while cobalt is enhanced by 1.5 dex. Heavier elements, including the lanthanides, generally follow the solar pattern but enhanced by 3 to 4 dex. Odd-Z elements are generally less abundant than their even-Z neighbours. With a few exceptions (e.g. Yb), the abundance pattern among the heavy elements is remarkably coherent, and resembles a displaced solar distribution.

Theoretical calculations of oscillator strengths and Land e g-factors made with the Cowan code are presented for the rare-earth ion Nd iii. The emphasis is on transitions in the optical region of the spectrum. Comparisons of previous ab initio calculations of this type for other lanthanides (e.g., La ii ,C eiii ,a nd Luii) with published experimental and theoretical data suggest that the accuracy of the log(gf) values for individual transi- tions should be about0:15 dex in the absence of signi- cant core polarization eects; theg-factors should be good to better than 5%, except in a few cases where term mix- ing is important. Applications of the data are made in the calculation of neodymium abundances in the atmospheres of the chemically peculiar stars HD 101065 (\Przybylski's star") and HD 122970.

Lutetium is one of the few nonvolatile elements whose solar photospheric abundance departs significantly from that derived from CI chondrites. We have applied the Cowan code to compute new oscillator strengths for Luii, and have included a correction for core polarization. The results have been used in a synthesis of the solar spectrum in the vicinity of features at \(\lambda _ \odot \)3397.062 and\(\lambda _ \odot \)6221.72. We find that the majority of the absorption in the ultraviolet feature is due to NH, making it unsuitable for extracting a reliable lutetium abundance. Our best fit to the low-noise Jungfraujoch spectrum for the weak, nine-component hyperfine Luii line at λ 6221.87 yields an abundance of +0.06 on a scale where log(H) = 12.00. This value is within 0.07 dex of the meteoritic result (+0.13). (These figures reflect the note added in proof below.)

We present the results from a detailed analysis of photometric and spectrophotometric data on five Seyfert 1 galaxies observed as a part of a recent reverberation mapping program. The data were collected at several observatories over a 140-day span beginning in 2010 August and ending in 2011 January. We obtained high sampling-rate light curves for Mrk 335, Mrk 1501, 3C120, Mrk 6, and PG2130+099, from which we have measured the time lag between variations in the 5100 Angstrom continuum and the H-beta broad emission line. We then used these measurements to calculate the mass of the supermassive black hole at the center of each of these galaxies. Our new measurements substantially improve previous measurements of MBH and the size of the broad line-emitting region for four sources and add a measurement for one new object. Our new measurements are consistent with photoionization physics regulating the location of the broad line region in active galactic nuclei., 45 pages, 5 figures. Accepted for publication in ApJ. For a brief video explaining the key results of this paper, see http://www.youtube.com/user/OSUAstronomy

We present velocity-resolved reverberation results for five active galactic nuclei. We recovered velocity-delay maps using the maximum entropy method for four objects: Mrk 335, Mrk 1501, 3C?120, and PG?2130+099. For the fifth, Mrk 6, we were only able to measure mean time delays in different velocity bins of the H? emission line. The four velocity-delay maps show unique dynamical signatures for each object. For 3C?120, the Balmer lines show kinematic signatures consistent with both an inclined disk and infalling gas, but the He II??4686 emission line is suggestive only of inflow. The Balmer lines in Mrk 335, Mrk 1501, and PG?2130+099 show signs of infalling gas, but the He II emission in Mrk 335 is consistent with an inclined disk. We also see tentative evidence of combined virial motion and infalling gas from the velocity-binned analysis of Mrk 6. The maps for 3C?120 and Mrk 335 are two of the most clearly defined velocity-delay maps to date. These maps constitute a large increase in the number of objects for which we have resolved velocity-delay maps and provide evidence supporting the reliability of reverberation-based black hole mass measurements.

We present the first results from a detailed analysis of photometric and spectrophotometric data on the narrow-line Seyfert 1 galaxy Mrk 335, collected over a 120-day span in the fall of 2010. From these data we measure the lag in the He II 4686 broad emission line relative to the optical continuum to be 2.7 \pm 0.6 days and the lag in the H\beta 4861 broad emission line to be 13.9 \pm 0.9 days. Combined with the line width, the He II lag yields a black hole mass, MBH = (2.6 \pm 0.8)\times 10^7 Msun. This measurement is consistent with measurements made using the H\beta 4861 line, suggesting that the He II emission originates in the same region as H\beta, but at a much smaller radius. This constitutes the first robust lag measurement for a high-ionization line in a narrow-line Seyfert 1 galaxy., Comment: 7 pages, 3 figures. Accepted for publication in ApJ Letters. For a brief video explaining the key results of this paper, see http://www.youtube.com/user/OSUAstronomy#p/a/u/0/Z2UCxQG5iOo

The star CD - 3312119, a suggested optical counterpart of X-ray source 3U 1727-33, has been studied photometrically. Brightness and color variations are observed on a time scale of days, but no regular pattern to these fluctuations is evident. Evidence for flares in U and B is discussed. Key words: X-ray sources-variable stars

The history of the University of Kansas' 27-inch reflecting telescope is traced from its beginnings in the drained, basement swimming pool of a talented Kansas City amateur astronomer, William Pitt, to its removal to its present location on the top of Lindley Hall in Lawrence under the supervision of Prof. N. W. Storer. Emphasis is placed on the early attempt by Dr. Dinsmore Alter to develop the University of Kansas' Observatory into a self-sustaining, first-class research facility and on those circumstances and events which have ultimately led to its evolution into a public relations showpiece and teaching telescope. As they enter, visitors to the University of Kansas' Observatory are greeted by a bronze plaque introducing them to the William Pitt 27-inch reflecting telescope. Few such individuals, upon leaving however, do so with an appreciation of the history and "romance," to use the word of former Professor of Astronomy, Dinsmore Alter, associated with this telescope. As Visiting Professor of Astronomy during the 1978-79 academic year, the writer had an opportunity to trace the development of the University's principal optical instrument and found it both a fascinating and, from an astronomer's point of view, often frustrating tale. This short article attempts to present the reader with a brief look at both these aspects of the story. While the study of astronomy at the University of Kansas dates from 1876, the first observatory building on campus was not erected until about 1885. Built on land deeded to the University by the State of Kansas, this structure, which really amounted to no more than a simple wooden shed with a slit roof, housed a 6-inch Alvan Clark refractor and a 2-inch transit telescope. The lifetime of the new observatory was extremely short, for within a year Gov. Robinson rescinded the gift of land upon which the building had been erected, and the structure was razed. From this time until 1919, the University had no permanent structure from which to make astronomical observations, although the teaching of astronomy was continued 1 Permanent address: Department of Physics, Benedictine College, Atchison, Kansas 66002. This content downloaded from 207.46.13.25 on Mon, 12 Sep 2016 04:20:18 UTC All use subject to http://about.jstor.org/terms 188 TRANSACTIONS OF THE KANSAS ACADEMY OF SCIENCES under the direction of a number of individuals, among them Prof. E. L. Nichols, the founder of the Physical Review. 1918-1935: THE ALTER YEARS In 1918, after serving two years with the artillery corps, Dr. Dinsmore Alter rejoined the University faculty, having been hired in 1916 just prior to the outbreak of hostilities between the United States and Germany. One of Prof. Alter's first official acts was to secure from the state legislature an appropriation of $3500 for the construction of a new observatory building and the purchase of a new 3-inch transit instrument and an equatorial mount for the 6-inch Clark refractor. The building, completed in the fall of 1919, occupied the site upon which the University's large Hoch Auditorium now stands. Throughout his 17 year association with the University, Alter, whose principal research interest was the computation of asteroid orbits, cherished the hope of creating an active program of asteroidal and cometary research in Lawrence. In a letter to then Chancellor Frank Strong dated May 28, 1919, he described the first step in fulfilling his dream: the construction of a 20-inch reflecting telescope. As outlined in his letter, Alter agreed to purchase, grind and figure the primary mirror for the instrument and then to donate it to the University, contingent upon the latter's purchase of an appropriate mounting and construction of an additional dome in which to house the telescope. A 1.6-inch thick blank was shortly thereafter purchased from the Pittsburg Plate Glass Co., and the grinding was begun in 1920, only to be abandoned soon afterward when it appeared that no mounting would be forthcoming from the University. In the fall of 1925, undaunted, Alter approached Mr. W. Y. Morgan, a member of the Kansas Board of Regents, with a plan for a new observatory and a proposal for a program of astronomical research for the University. To implement the proposal, which had been endorsed by some of the leading astronomers of the day, including W. S. Adams of Mt. Wilson, E. B. Frost of Yerkes, R. G. Aitken of Lick and Harlow Shapley of Harvard, required an estimated total of $850,000, $210,000 of which Alter hoped to secure by an outright gift to purchase, among other things, a 36-inch reflector; the remainder of the $850,000 was to go into an endowment fund, the interest from which was to be used to provide salaries for two additional astronomers and a staff of computers, whose primary efforts would be directed towards the determination of accurate asteroid orbits. As with his previous efforts, Alter was not successful in securing the necessary financial backing for his program, and no equipment or staff was added at this time. Indeed, in 1926, the Observatory was razed for the second time to make room for a new auditorium (Hoch), and rebuilt west of Marvin Hall. It was in the same year, 1926, that Alter (probably through the intercesThis content downloaded from 207.46.13.25 on Mon, 12 Sep 2016 04:20:18 UTC All use subject to http://about.jstor.org/terms VOLUME 83, NUMBER 4 189 ~ ~':":;? jk~l~ ~r* .I.rr *t? i~-.JWrt : t i?[l~y i

A set of computer programs, VIRIS, which has been developed to aid in the reduction of IUE spectroscopic data is described. Various methods of filtering and smoothing the IUE data are discussed, and spectral rectification routines are described. Routines which automatically locate and store the positions of absorption lines are described, as are routines which can be used to assist in the determination of IUE wavelength-scale errors. The merits of the VIRIS system are discussed, and other packages are reviewed.

Spectroscopic observations of the B1.5 supergiant Wra 977 from several observing seasons are described. The star has pronounced stellar wind characteristics which make orbital determination difficult. Lines which are considered most likely to represent orbital motions show velocities antiphased with the X-ray pulsar for the suggested 35.0-day period. A forced fit to the X-ray determined orbit yields a mass ratio of about 20 and implies masses of greater than 30 and greater than 1.5 solar masses for the stars. Weak He II 4686 A emission is detected. No evidence is found for profound periastron effects in the e = 0.44 orbit. Other spectroscopic information and the evolutionary status of the system are discussed. Similar considerations apply to the 41.37-day period.

Radial-velocity measurements for the principal emission features in the Sco X-1 spectrograms of Mook, Hiltner, and Lynds are discussed. Plots of the radial velocities of H..cap alpha.., H..beta.., and He ii lambda4686 as a function of phase for the 0/sup d/787313 period of Gottlieb, Wright, and Liller are presented. In spite of the large scatter in the data, the time-dependent behavior of the radial velocities for the Balmer lines appears to confirm the binary nature of Sco X-1. In contrast to the report of Cowley and Crampton, no periodic variation in the radial velocity of the He ii lambda4686 line is observed. (AIP)

UBV photometry of WRA 977 on 36 nights between January and July 1974 reveals activity on a time scale of days at the 0.1 mag level; no activity greater than approx.0.01 mag is observed on a time scale of minutes. Correlogram and periodogram analyses of the light curve reveal no persistent periodic variations of significant amplitude. (AIP)