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We report the discovery of the new gravitational lens system HE~0230$-$2130, a QSO at redshift $z=2.162$ consisting of at least five distinct components. Three of these are clearly lensed images of the QSO, one is most likely the lensing galaxy, while for the fifth component the identity is unclear: It could be a fourth QSO image (if so, then highly reddened), or another intervening galaxy, or a superposition of the two. Differential reddening seems to be important also for the first three QSO images. The surface density of faint galaxies near the QSO appears to be enhanced by a factor of $\ga 2$, indicating the presence of a distant cluster close to the line of sight., Comment: 4 pages, accepted by A&A, Letters to the Editor

We report the discovery and ground based observations of the new gravitational lens CTQ 414. The source quasar lies at a redshift of z = 1.29 with a B magnitude of 17.6. Ground based optical imaging reveals two point sources separated by 1.2 arcsec with a magnitude difference of roughly 1 mag. Subtraction of two stellar point spread functions from images obtained in subarcsecond seeing consistently leaves behind a faint, residual object. Fits for two point sources plus an extended object places the fainter object collinear with the two brighter components. Subsequent HST/NICMOS observations have confirmed the identification of the fainter object as the lensing galaxy. VLA observations at 8.46 GHz reveal that all components of the lensing system are radio quiet down to the 0.2 mJy flux level., Comment: Latex, 18 pages including 2 ps figures; accepted for publication in AJ

H band observations with a spatial resolution of 0.15" carried out with the Canada-France-Hawaii Telescope adaptive optics system show a galaxy between the components of the double BAL quasar SBS 1520+530, thereby confirming this system as a gravitational lens. The galaxy is located 0.40" from the fainter of the two QSO images and is offset 0.12" from the line joining them. The H magnitude of the lensing galaxy is ~1 mag fainter than expected from the velocity dispersion derived for the lensing galaxy were it at z = 0.71 or z = 0.81, the redshifts of the two absorption line systems., Comment: 11 pages latex including one table and 2 postscript figures. Corrected typo. Accepted by AJ. Also available at http://www.hia.nrc.ca/science/preprint/preprint.html

We present results of a survey of a 6-square-degree region near l=60, b=0 to search for distant Milky Way Cepheids. Few MW Cepheids are known at distances >~ R_0, limiting large-scale MW disk models derived from Cepheid kinematics; this work was designed to find a sample of distant Cepheids for use in such models. The survey was conducted in the V and I bands over 8 epochs, to a limiting I~=18, with a total of ~ 5 million photometric observations of ~ 1 million stars. We present a catalog of 578 high-amplitude variables discovered in this field. Cepheid candidates were selected from this catalog on the basis of variability and color change, and observed again the following season. We confirm 10 of these candidates as Cepheids with periods from 4 to 8 days, most at distances > 3 kpc. Many of the Cepheids are heavily reddened by intervening dust, some with implied extinction A_V > 10 mag. With a future addition of infrared photometry and radial velocities, these stars alone can provide a constraint on R_0 to 8%, and in conjunction with other known Cepheids should provide good estimates of the global disk potential ellipticity., Comment: 18 pages, 4 tables, 13 figures (LaTeX / AASTeX)

A "friends-of-friends" percolation algorithm has been used to extract a catalogue of drho/rho = 80 density enhancements (groups) from the six slices of the Las Campanas Redshift Survey (LCRS). The full catalogue contains 1495 groups and includes 35% of the LCRS galaxy sample. A statistical sample of 394 groups has been derived by culling groups from the full sample which either are too close to a slice edge, have a crossing time greater than a Hubble time, have a corrected velocity dispersion of zero or less, or contain a 55 arcsec "orphan" (a galaxy with a "faked" redshift excluded from the original LCRS redshift catalogue due to its proximity --- i.e., within 55 arcsec --- of another galaxy). Median properties derived from the statistical sample include: line-of-sight velocity dispersion sigma_los = 164 km/s, crossing time t_cr = 0.10/H_0, harmonic radius R_h = 0.58/h Mpc, pairwise separation R_p = 0.64/h Mpc, virial mass M_vir = (1.90x10^13)/h M_sun, total group R-band luminosity L_tot = (1.40x10^11)/h^2 L_sun, and R-band mass-to-light ratio M/L = 153h M_sun/L_sun., Comment: 11 pages, LaTeX. A poster paper which appeared at the the 12th Potsdam Cosmology Workshop, "Large Scale Structure: Tracks and Traces". A 2-page writeup of the poster will appear in the conference proceedings and is presently available at http://manaslu.astro.utoronto.ca:80/~lin/ConfProc/ConfProc.html and at http://www.aip.de:8080/~tucker/ConfProc/ConfProc.html

The V=16.9 quasar FBQ 0951+2635 at redshift z=1.24 appears double on CCD exposures taken in subarcsecond seeing. The two objects are separated by 1.1" and differ in brightness by 0.9 mag. VLA observations show the radio source to be double with the same separation and position angle. Spectra taken with the Keck II telescope show the two components to have nearly identical emission line spectra, but with somewhat different absorption line systems. Subtraction of two stellar point spread functions from the pair of components consistently leaves a residual object. Depending upon whether this third object is extended or a point source it may be as much as 1/10 or as little as 1/100 as bright as the brighter QSO component. The observations leave no doubt that the 2 brighter objects are gravitationally lensed images of the same quasar. The third object might be either the lensing galaxy or a third image of the quasar, but both interpretations have serious shortcomings., Comment: LaTex, 19 pages including 5 ps figures; submitted to AJ

A catalog of Cepheid variables is used to probe the kinematics of the Galactic disk. Radial velocities are measured for eight distant Cepheids toward l = 300; these new Cepheids provide a particularly good constraint on the distance to the Galactic center, R_0. We model the disk with both an axisymmetric rotation curve and one with a weak elliptical component, and find evidence for an ellipticity of 0.043 +/- 0.016 near the Sun. Using these models, we derive R_0 = 7.66 +/- 0.32 kpc and v_circ = 237 +/- 12 km/s. The distance to the Galactic center agrees well with recent determinations from the distribution of RR Lyrae variables, and disfavors most models with large ellipticities at the solar orbit., Comment: 36 pages, LaTeX, 10 figures

Gravitational lensing is now widely and successfully used to study a range of astronomical phenomena, from individual objects, like galaxies and clusters, to the mass distribution on various scales, to the overall geometry of the Universe. Here we describe and assess the use of gravitational lensing as ``gold standards'' in addressing one of the fundamental problems in astronomy, the determination of the absolute distance scale to extragalactic objects. This is commonly parameterized by the Hubble constant, $H_0$, the current expansion rate of the Universe. The elegance of the underlying geometrical principle of the gravitational lensing method combined with the recent advances in observations and modelling makes it a very promising technique for measuring $H_0$., Comment: 15 pages, LaTeX, figues included; To appear in October issue of Astronomy and Geophysics, the Journal of the Royal Astronomical Society

We have designed and built a new type of CCD that we call an orthogonal transfer CCD (OTCCD), which permits parallel clocking horizontally as well as vertically. The device has been used successfully to remove image motion caused by atmospheric turbulence at rates up to 100 Hz, and promises to be a better, cheaper way to carry out image motion correction for imaging than by using fast tip/tilt mirrors. We report on the device characteristics, and find that the large number of transfers needed to track image motion does not significantly degrade the image either because of charge transfer inefficiency or because of charge traps. For example, after 100 sec of tracking at 100 Hz approximately 3% of the charge would diffuse into a skirt around the point spread function. Four nights of data at the Michigan-Dartmouth-MIT (MDM) 2.4-m telescope also indicate that the atmosphere is surprisingly benign, in terms of both the speed and coherence angle of image motion. Image motion compensation improved image sharpness by about 0.5 arcsec in quadrature with no degradation over a field of at least 3 arcminutes., Comment: 21 pages, AASTeX Latex, including 15 Postscript figures, to be published in PASP

We report the discovery of a new gravitationally lensed radio source. Radio maps of MG0751+2716 show four lensed images, which, at higher resolution, are resolved into long arcs of emission. A group of galaxies is present in optical images, including the principal lensing galaxy, with a much brighter galaxy just a few arcseconds away. We have measured the redshift of this brighter galaxy. No optical counterpart to the background source has been detected. Lens models that can readily reproduce the lensed image positions all require a substantial shear component. However, neither the very elongated lens nor the bright nearby galaxy are correctly positioned to explain the shear. Lens models which associate the mass with the light of galaxies in the group can produce an acceptable fit, but only with an extreme mass-to-light ratio in one of the minor group members., Comment: 1 Latex aaspp4 manuscript, 17 pages with 5 postscript figures. Submitted to AJ 1997.02.19; accepted 1997.04.15 . Mostly stylistic changes since the first submission, with a few minor changes in content and the tables

Presented are measurements of the observed redshift-space galaxy-galaxy autocorrelation function, xi(s), for the Las Campanas Redshift Survey (LCRS). For separations 2.0/h Mpc < s < 16.4/h Mpc, xi(s) can be approximated by a power law with slope of -1.52 +/- 0.03 and a correlation length of s_0 = (6.28 +\- 0.27)/h Mpc. A zero-crossing occurs on scales of roughly 30 - 40/h Mpc. On larger scales, xi(s) fluctuates closely about zero, indicating a high level of uniformity in the galaxy distribution on these scales. In addition, two aspects of the LCRS selection criteria - a variable field-to-field galaxy sampling rate and a 55 arcsec galaxy pair separation limit - are tested and found to have little impact on the measurement of xi(s). Finally, the LCRS xi(s) is compared with those from numerical simulations; it is concluded that, although the LCRS xi(s) does not discriminate sharply among modern cosmological models, redshift-space distortions in the LCRS xi(s) will likely provide a strong test of theory., Comment: 5 pages, LaTeX, 8 postscript figures, and plotting.sty included. Text and figures are also available at http://manaslu.astro.utoronto.ca:80/~lin/JournalPapers/JournalPapers.html and at http://www.aip.de:8080/~tucker/JournalPapers/JournalPapers.html Accepted for publication by MNRAS

Optical photometry is presented for the quadruple gravitational lens PG1115+080. A preliminary reduction of data taken from November 1995 to June 1996 gives component ``C'' leading component ``B'' by 23.7+/-3.4 days and components ``A1'' and ``A2'' by 9.4 days. A range of models has been fit to the image positions, none of which gives an adequate fit. The best fitting and most physically plausible of these, taking the lensing galaxy and the associated group of galaxies to be singular isothermal spheres, gives a Hubble constant of 42 km/s/Mpc for Omega=1, with an observational uncertainty of 14%, as computed from the B-C time delay measurement. Taking the lensing galaxy to have an approximately E5 isothermal mass distribution yields H0=64 km/sec/Mpc while taking the galaxy to be a point mass gives H0=84 km/sec/Mpc. The former gives a particularly bad fit to the position of the lensing galaxy, while the latter is inconsistent with measurements of nearby galaxy rotation curves. Constraints on these and other possible models are expected to improve with planned HST observations., Comment: Submitted to Ap. J. Letters (Received 96 September 9); 14 pages including figures; uses aaspp4.sty (included); also available (with supplementary figures and tables) at http://arcturus.mit.edu/~schech/pg1115.html

The Las Campanas Redshift Survey (LCRS) contains 23697 galaxies, with an average redshift $z = 0.1$, distributed over six $1.5\arcdeg$ by $80\arcdeg$ slices in the North and South galactic caps. We have computed the power spectrum $P(k)$ for LCRS galaxies over wavelengths $\lambda = 2\pi / k = 5 - 400\ h^{-1}$~Mpc. The LCRS $P(k)$ may be approximated as $\propto k^{-1.8 \pm 0.1}$ for small scales $\lambda = 5 - 30\ h^{-1}$~Mpc, changing to $\propto k^{1 \pm 1}$ for large scales $\lambda \approx 200 - 400\ h^{-1}$~Mpc. The overall amplitude corresponds to $\sigma_8 = 1.0 \pm 0.1$ in redshift space. Comparisons to the power spectra of other redshift surveys will be presented; the LCRS results agree best with those from the combined Center for Astrophysics and Southern Sky redshift surveys. We find evidence for type- dependent clustering differences in the LCRS, such that galaxies brighter than about $M^* - 1$ appear about 50\% more strongly clustered than those fainter, and that a sample of emission galaxies shows 30\% weaker clustering than the full LCRS sample. On large scales $\lambda \gtrsim 40\ h^{-1}$~Mpc, we have also fit the LCRS results to various linear CDM models, and find that a number of them could meet the constraints set by the LCRS power spectrum, the Hubble constant range $0.5 \lesssim h \lesssim 0.8$, the abundance of galaxy clusters, and the reasonable assumption that LCRS galaxies are roughly unbiased tracers of the mass, relative to the normalization provided by the 4-year COBE DMR data. The possibilites include open CDM or flat non-zero cosmological-constant CDM models with $\Omega_0 \approx 0.4-0.6$ and shape parameter $\Gamma \approx 0.2-0.3$, as well as flat $\Omega_0 = 1$ models with massive neutrino density $\Omega_\nu \approx 0.2-0.3$ or a spectral tilt $n \approx 0.7-0.8$. (abridged), Comment: 48 pages, including 15 of 16 postscript figures, uses AASTEX v4.0 style files, to appear in ApJ. The full paper is available at http://manaslu.astro.utoronto.ca/~lin/lcrs.html (North America) and http://www.aip.de:8080/~tucker/lcrs-mirror.html (Europe)

The Las Campanas Redshift Survey (LCRS) consists of 26418 redshifts of galaxies selected from a CCD-based catalog obtained in the $R$ band. The survey covers over 700 square degrees in 6 strips, each 1.5$\arcdeg$ x 80$\arcdeg$, three each in the North and South galactic caps. The median redshift in the survey is about 30000 km~s$^{-1}$. Essential features of the galaxy selection and redshift measurement methods are described and tabulated here. These details are important for subsequent analysis of the LCRS data. Two dimensional representations of the redshift distributions reveal many repetitions of voids, on the scale of about 5000 km~s$^{-1}$, sharply bounded by large walls of galaxies as seen in nearby surveys. Statistical investigations of the mean galaxy properties and of clustering on the large scale are reported elsewhere. These include studies of the luminosity function, power spectrum in two and three dimensions, correlation function, pairwise velocity distribution, identification of large scale structures, and a group catalog. The LCRS redshift catalog will be made available to interested investigators at an internet web site and in archival form as an Astrophysical Journal CD-ROM., Comment: 40 pages, including 11 of 17 postscript figures, uses AASTEX v4.0 style files, to appear in ApJ. The full paper, as well as the LCRS redshift catalog, are available at http://manaslu.astro.utoronto.ca/~lin/lcrs.html (North America) and at http://www.aip.de:8080/~tucker/lcrs-mirror.html (Europe)

We present the $R$-band luminosity function for a sample of 18678 galaxies, with average redshift $z = 0.1$, from the Las Campanas Redshift Survey. The luminosity function may be fit by a Schechter function with $M^* = -20.29 \pm 0.02 + 5 \log h$, $\alpha = -0.70 \pm 0.05$, and $\phi^* = 0.019 \pm 0.001 \ h^3$~Mpc$^{-3}$, for absolute magnitudes $-23.0 \leq M - 5 \log h \leq -17.5$. We compare our luminosity function to that from other redshift surveys; in particular our normalization is consistent with that of the Stromlo-APM survey, and is therefore a factor of two below that implied by the $b_J \approx 20$ bright galaxy counts. Our normalization thus indicates that much more evolution is needed to match the faint galaxy count data, compared to minimal evolution models which normalize at $b_J \approx 20$. Also, we show that our faint-end slope $\alpha = -0.7$, though ``shallower'' than typical previous values $\alpha = -1$, results primarily from fitting the detailed shape of the LCRS luminosity function, rather than from any absence of intrinsically faint galaxies from our survey. Finally, using [OII] 3727 equivalent width $W_{\lambda} = 5$~\AA \ as the dividing line, we find significant differences in the luminosity functions of emission and non-emission galaxies, particularly in their $\alpha$ values. Emission galaxies have Schechter parameters $M^* = -20.03 \pm 0.03 + 5 \log h$ and $\alpha = -0.9 \pm 0.1$, while non-emission galaxies are described by $M^* = -20.22 \pm 0.02 + 5 \log h$ and $\alpha = -0.3 \pm 0.1$. (abridged abstract), Comment: 41 pages, including 13 postscript figures, uses AASTEX v4.0 style files. Important clarification of R-band definition, plus correction of luminosity densities and updated references. Main conclusions unchanged. Final version to appear in ApJ

The primary distance indicators are established in our Galaxy and the Local Group. There are at least four different methods which give good distances: methods using proper motions, RR Lyraes, Cepheid variables, and Type II supernovae. However the data on independent distances is very fragmentary, due partly to nature and partly to technological limits. As a result the data are rarely put together in a consistent way; instead, the discussion of distance scales is often focused on one or two methods or on individual objects. Hence the question: what is the current situation with our overall knowledge of distances to the nearby galaxies? We try to answer this question by combining the fragmentary data from all four methods for fifteen objects: the galactic center, the globular clusters M2, M3, M4, M13, M22, M92, and 47 Tuc, the galaxies IC1613, M31, M33, M81, M100, and M101, and the Large Magellanic Cloud. We pay special attention to covariances among the different distance estimates. This most complete combination to date shows that all four methods are consistent within their random and systematic uncertainties., Comment: 28 pages of uuencoded compressed postscript text and figures. To appear in the Astronomical Journal (December 1995)

Asserts that public policy analysis has a time-honored tradition in civics education. Provides a four-part teachers' rationale for including the study of child-labor legislation in social studies courses. Includes a five-part classroom format for teaching public policy analysis. (CFR)

In the United States, the Bill of Rights is most often thought of as the charter that establishes individual rights in categories such as "freedom of expression" and "rights of the accused." In this essay it is argued that this conception of the Bill of Rights, while perhaps acceptable for constitutional law, does not provide an adequate historical interpretation. This paper seeks to examine the eighteenth-century meaning of the Bill of Rights and the particular rights provided within it. The eighteenth-century conception of rights was more community-oriented than the individual-oriented conception of rights today. A term that describes the eighteenth-century conception of the Bill of Rights is "protected self-government." This concept contains two strands: civil liberties and the right to self-government; and the provisions of the Bill of Rights were designed not only to guarantee civil liberties but also to tie those liberties into the political right of self-government. The right to a trial by jury is used as an illustration. In the late eighteenth century the Founders viewed the right of trial by jury as a right belonging not only to the accused but also to the citizen as juror. It also is contended that there are five basic sources of the concept of protected self-government and its particular provisions contained in the U.S. Bill of Rights. These are English law, Puritan and Whig consent theory, American colonial charters of liberties, first American state constitutional bills of rights, and the constitutional ratification debate of 1787-88. Each of these is considered in turn as it relates to the concept of "protected self-government." (DB)

"The Federalist" should be understood as a document with three purposes. It is: a campaign document designed to win popular support for the proposed Constitution; a serious work of political thought, analyzing the nature of free societies; and the authoritative commentary on the Constitution. This guide is intended to help readers of "The Federalist" to better understand it through an explanation of its historical context, its use of rhetoric, and its underlying political theory; and a consideration of how these elements interact and reinforce one another. Aspects of the debate between the Federalists and Antifederalists that specifically affected New York State are focused upon. Four of the essays that compose "The Federalist" (Numbers 10, 51, 37, and 39) are examined in some detail. (DB)