Harmonizing the RR Lyrae and Clump Distance Scales - Stretching the Short Distance Scale to Intermediate Ranges?

I explore the consequences of making the RR Lyrae and clump giant distance scales consistent in the solar neighborhood, Galactic bulge and Large Magellanic Cloud (LMC). I employ two major assumptions: 1) that the absolute magnitude - metallicity, M_V(RR) - [Fe/H], relation for RR Lyrae stars is universal, and 2) that absolute I-magnitudes of clump giants, M_I(RC), in Baade's Window are known (e.g., can be inferred from the local Hipparcos-based calibration or theoretical modeling). A comparison between the solar neighborhood and Baade's Window sets M_V(RR) at [Fe/H] = -1.6 in the range (0.59 +/- 0.05, 0.70 +/- 0.05), somewhat brighter than the statistical parallax solution. More luminous RR Lyrae stars imply younger ages of globular cluster, which would be in better agreement with the conclusions from the currently favored stellar evolution and cosmological models. A comparison between Baade's Window and the LMC sets the M_I^{LMC}(RC) in the range (-0.33 +/- 0.09, -0.53 +/- 0.09). The distance modulus to the LMC, mu^{LMC}, is between 18.24 +/- 0.08 and 18.44 +/- 0.07. Unlike M_I^{LMC}(RC), this range in mu^{LMC} does NOT depend on the adopted value of the dereddened LMC clump magnitude, I_0^{LMC}(RC). I argue that the currently available information is insufficient to select the correct distance scale with high confidence.Comment: version accepted to MNRAS, added discussion about the dependence of the results on theoretical assumptions and observational input, stressed that the derived range of the LMC distance modulus between 18.24 and 18.44 is insensitive to the controversial dereddened I-magnitude of the LMC clump giant

The Distance to the Large Magellanic Cloud

I demonstrate that the two unexpected results in the local Universe: anomalous intrinsic (V-I)_0 colors of RR Lyrae stars and clump giants in the Galactic center, and very short distances to Magellanic Clouds inferred from clump giants, can be at least partially resolved with a modified coefficient of selective extinction A_V/E(V-I). With this modification, I find a new clump-giant distance modulus to the Large Magellanic Cloud, mu_{LMC} = 18.27 +/- 0.07, which is 0.09 larger than the Udalski (1998b) result. When distance estimates from the red clump, RR Lyrae stars and the eclipsing binary HV2274 are combined, one obtains mu_{LMC} = 18.31 +/- 0.04 (internal).Comment: less detailed and more review-style version of ApJ Letter (528, L9), to be published in the ASP Conference Series Vol. 203, 1999: ``The Impact of Large Scale Surveys on Pulsating Star Research'', L. Szabados and D. Kurtz, ed

A Test for the Origin of Quasar Redshifts

It is commonly accepted that quasar redshifts have a cosmological character and that most of the quasars are at Gigaparsec distances. However, there are some cases where several quasars with completely different redshifts and a nearby active galaxy are aligned in a certain way or occupy a very small patch on the sky, which is claimed by some authors to be unlikely to happen by chance. Is there a small subset of quasars with non-cosmological redshifts? For quasars apparently associated with galaxies, we consider two scenarios for the origin of their redshift: 1. a standard, cosmological scenario, 2. a velocity-induced Doppler shift of a nearby object's spectrum (local, ejection scenario). We argue for a simple astrometric test which can distinguish between these two sources of quasar redshifts by constraining their proper motions. We give the predictions for the maximum possible proper motions of a quasar for the cosmological and local scenarios of the origin of their redshifts. We apply these theoretical results to the Bukhmastova (2001) catalog, which contains more than 8000 close QSO-galaxy associations. In the standard interpretation of quasar redshifts, their typical proper motions are a fraction of micro arc-second, and beyond the reach of planned astrometric missions like GAIA and SIM. On the other hand, the quasars ejected from local AGNs at velocities close to the speed of light would have proper motions 5-6 orders of magnitude larger, which would easily be measurable with future astrometric missions. The distributions of proper motions for the cosmological and local scenarios are very well separated. Moreover, the division corresponds nicely to the expected accuracy from GAIA and SIM.Comment: results unchanged, minor additions, 10 pages, 6 figures, 1 table, accepted to MNRA

Total to Selective Extinction Ratios and Visual Extinctions from Ultraviolet Data

We present determinations of the total to selective extinction ratio R_V and visual extinction A_V values for Milky Way stars using ultraviolet color excesses. We extend the analysis of Gnacinski and Sikorski (1999) by using non-equal weights derived from observational errors. We present a detailed discussion of various statistical errors. In addition, we estimate the level of systematic errors by considering different normalization of the extinction curve adopted by Wegner (2002). Our catalog of 782 R_V and A_V values and their errors is available in the electronic form on the World Wide Web.Comment: 20 pages, 7 figures, submitted to Acta Astronomic

Comparison of topographical changes associated with overnight wear of inverted silicone hydrogel contact lenses of different powers

Purpose: Previously conducted studies have demonstrated significant topographical changes following overnight wear of both normally configured (non-inverted) and inverted -6.00D silicone hydrogel lenses. Further, a distinct difference in topography was realized between eyes wearing the inverted vs non-inverted lenses. These results suggest that silicone hydrogel lenses may be sufficiently rigid to potentially effect predictable changes in corneal topography following overnight wear. This investigation was designed to study the effects of overnight wear of -9.00D silicone hydrogel lenses to evaluate changes in corneal topography and to compare these results with previously collected data to determine if they result in greater changes in topography due to increased rigidity of the lenses. Methods: Baseline corneal topography data was collected for N = 11 subjects. The subjects were then fit with -9.00D Focus Night & Day (CibaVision) silicone hydrogel lenses. All subjects, who were recruited based on their participation in the initial study, wore a non-inverted lens on one eye and an inverted lens on the other eye, to match the conditions of the previous study, which was determined by a randomization schedule. Lenses were removed following 12hrs of continuous wear, including 8hrs of overnight wear. Following removal of the contact lenses, corneal topography data was collected, and a comfort survey was completed comparing the subjects\u27 perception of comfort with both the non-inverted and inverted contact lenses. Results: The inverted -9.00D lens resulted in significantly (p Conclusions: Greater corneal flattening was realized with inverted silicone hydrogel contact lenses vs non-inverted lenses. Further, the effect was greater with higher powered minus lenses. These data suggest that planned corneal reshaping to correct for refractive error may occur with appropriately designed silicone hydrogel lenses. Both inverted and non-inverted contact lenses were well-tolerated during overnight wear

Roman Catholic crusading in ten years of Triumph, 1966-1976: A history of a lay-directed, radical Catholic journal

Scope and Method of Study: The purpose of this study was to explicate the Roman Catholic views of Triumph, a lay-directed Catholic journal. The principal source was the journal. In addition, the research was dependent upon interviews, books published by the editors, papal encyclicals, Vatican Council II documents, and two special collections. The primary research was complimented by extensive secondary research.Findings and Conclusions: The purpose of Triumph 's editors was to convert America to the Roman Catholic faith and construct a confessional state. That is, they wanted to subject the public order to the authority of Christ's vicar, the pope. They believed that the American political order--because it gave authority to the people, rather than Christ, and separated Church and state--was an inherently secular and relativist order, and thus, was an obstacle to virtue. The confessional state, in contrast, aided virtue and thereby promoted the salvation of its members. The confessional state, they noted, was an act of love. The thesis of this dissertation is that Triumph 's editors were radical. Their views--essentially calling for a regime change--were militant and extraordinary in the context of late twentieth-century America. Two sub-theses of this dissertation are that the editors did more than sustain a journal, but actually founded a movement dedicated to their radical goals, and that the journal, despite its sectarian views, was important. Their views and actions exhibited the tension that is to exist, supposedly, between the Roman Catholic Church and the modern pluralist and secular state. Catholics have dual citizenship, to the Church of Rome and to their country. The obligations to the former, the Church teaches, supersede the latter when their interests conflict. A Catholic revival in America, rooted in such a tension, could rightly be traced to Triumph

The Determination Of Reddening From Intrinsic VR Colors Of RR Lyrae Stars

New R-band observations of 21 local field RR Lyrae variable stars are used to explore the reliability of minimum light (V-R) colors as a tool for measuring interstellar reddening. For each star, R-band intensity mean magnitudes and light amplitudes are presented. Corresponding V-band light curves from the literature are supplemented with the new photometry, and (V-R) colors at minimum light are determined for a subset of these stars as well as for other stars in the literature. Two different definitions of minimum light color are examined, one which uses a Fourier decomposition to the V and R light curves to find (V-R) at minimum V-band light, (V-R)_{min}^F, and the other which uses the average color between the phase interval 0.5-0.8, (V-R)_{min}^{\phi(0.5-0.8)}. From 31 stars with a wide range of metallicities and pulsation periods, the mean dereddened RR Lyrae color at minimum light is (V-R)_{min,0}^F = 0.28 pm 0.02 mag and (V-R)_{min,0}^{\phi(0.5-0.8)} = 0.27 pm 0.02 mag. As was found by Guldenschuh et al. (2005) using (V-I) colors, any dependence of the star's minimum light color on metallicity or pulsation amplitude is too weak to be formally detected. We find that the intrinsic (V-R) of Galactic bulge RR Lyrae stars are similar to those found by their local counterparts and hence that Bulge RR0 Lyrae stars do not have anomalous colors as compared to the local RR Lyrae stars.Comment: accepted by A