Multi-Dimensional Ideology in the Multi-Member District: An Analysis of the Arizona Legislature

http://www.truman.missouri.edu/ipp/publications/index.asp?ViewBy=DateAmerican state legislatures provide considerable institutional variation for testing theories of legislative representation, and one such feature is the multi-member district system (MMD). Whereas the U.S. House and most American state legislatures use the single member district system (SMD) in which a single legislator represents one geographic district, several state legislatures still use a system in which more than one legislator is elected from the same district in the same election. Although there can be considerable variation in the rules for such MMDs, one structure common to many state legislatures is a situation in which multiplecandidates run against each other for two seats from one district, and the two receiving the most votes are elected. Clearly, the electoral game is quite different in a situation in which a candidate is likely to be running against not only members of other parties but also another candidate of the same party. The incentives inherent in such a system are quite different than those for a legislator in an SMD, and it likely that such incentives change legislative representation in a number of ways.Includes bibliographical reference

Stellar Evolutionary Models for Magellanic Clouds

We supplement current evolutionary computations concerning Magellanic Cloud stars by exploring the evolutionary behavior of canonical stellar models (i.e.,with inefficient core overshooting) with metallicities suitable for stars in the Clouds. After discussing the adequacy of the adopted evolutionary scenario, we present evolutionary sequences as computed following a selected sample of stellar models in the mass range 0.8-8 Mo from the Main Sequence till the C ignition or the onset of thermal pulses in the advanced Asymptotic Giant Branch phase. On this basis, cluster isochrones covering the range of ages from 100 Myr to 15 Gyr are presented and discussed. To allow a comparison with evolutionary investigations appeared in the recent literature, we computed additional sets of models which take into account moderate core overshooting during the H burning phase, discussing the comparison in terms of current uncertainties in the stellar evolutionary models. Selected predictions constraining the cluster ages are finally discussed, presenting a calibration of the difference in magnitude between the luminous MS termination and the He burning giants in terms of cluster age. Both evolutionary tracks and isochrones have been made available at the node http://gipsy.cjb.net as a first step of a planned ``Pisa Evolutionary Library''.Comment: 11 pages, 9 eps figures, A&A accepted, evolutionary tracks and isochrones available at http://gipsy.cjb.net at the link ``Pisa Evolutionary Library'

How Brexit can give Scotland, Wales and Northern Ireland more policymaking power

As the result of last week's election begins to sink in, one thing on the minds of politicians in Scotland, Wales and Northern Ireland is the fate of devolved authority after Brexit. Anthony M. Bertelli (Bocconi and Penn State) asks how Brexit can give them more policymaking power. Prime Minister Boris Johnson endorsed devolved authority during a September trip to Scotland: “We are going to maximise the power of the North. And we are going to make sure that it is people here who are in control over the things that matter to them.” Michael Russell, Scotland’s Secretary for Government Business and Constitutional Relations, saw things differently. He claimed that Westminster is “determined” to roll back devolution in favour of a “more centralised state.

Spectroscopic Confirmation of a z=2.79 Multiply Imaged Luminous Infrared Galaxy Behind the Bullet Cluster

We report spectroscopic confirmation and high-resolution infrared imaging of a z=2.79 triply-imaged galaxy behind the Bullet Cluster. This source, a Spitzer-selected luminous infrared galaxy (LIRG), is confirmed via polycyclic aromatic hydrocarbon (PAH) features using the Spitzer Infrared Spectrograph (IRS) and resolved with HST WFC3 imaging. In this galaxy, which with a stellar mass of M*=4e9 Msun is one of the two least massive ones studied with IRS at z>2, we also detect H_2 S(4) and H_2 S(5) pure rotational lines (at 3.1 sigma and 2.1 sigma) - the first detection of these molecular hydrogen lines in a high-redshift galaxy. From the molecular hydrogen lines we infer an excitation temperature T=377+68-84 K. The detection of these lines indicates that the warm molecular gas mass is 6(+36-4)% of the stellar mass and implies the likely existence of a substantial reservoir of cold molecular gas in the galaxy. Future spectral observations at longer wavelengths with facilities like the Herschel Space Observatory, the Large Millimeter Telescope, and the Atacama Pathfinder EXperiment (APEX) thus hold the promise of precisely determining the total molecular gas mass. Given the redshift, and using refined astrometric positions from the high resolution imaging, we also update the magnification estimate and derived fundamental physical properties of this system. The previously published values for total infrared luminosity, star formation rate, and dust temperature are confirmed modulo the revised magnification; however we find that PAH emission is roughly a factor of five stronger than would be predicted by the relations between the total infrared and PAH luminosity reported for SMGs and starbursts in Pope et al. (2008).Comment: 8 pages, 4 figures, accepted to Ap

A Stromgren view of the multiple populations in globular clusters

We discuss a variety of photometric indices assembled from the uvby Stromgren system. Our aim is to examine the pros and cons of the various indices to find the most suitable one(s) to study the properties of multiple populations in globular clusters (GCs) discovered by spectroscopy. We explore in particular the capabilities of indices like m_1 and c_y at different metallicities. We define a new index delta_4=(u-v)-(b-y) to separate first and second stellar generations in GCs of any metal abundance, since it keeps the sensitivity to multiple stellar populations over all the metallicity range and at the same time minimizes the sensitivity to photometric errors. We detecte clear differences in the red giant branches of the GCs examined, like skewness or bi/multi-modality in color distribution. We connect the photometric information with the spectroscopic results on O, Na abundances we obtained in our survey of GCs. Finally, we compute the effects of different chemical composition on the Stromgren filters and indices using synthetic spectra.Comment: Accepted for publication on Astronomy and Astrophysics. Figures 1,3,5 degraded in resolutio

An empirical test of the theoretical population corrections to the Red Clump absolute magnitude

The mean absolute magnitude of the local red clump (RC) is a very well determined quantity due to the availability of accurate HIPPARCOS parallaxes for several hundred RC stars, potentially allowing it to be used as an accurate extra-galactic distance indicator. Theoretical models predict that the RC mean magnitude has non-linear dependencies on both age and metallicity. This suggests that a population correction, based on the star formation rate (SFR) and age-metallicity relation (AMR) of a particular system, should be applied to the local RC magnitude before it can be compared to the RC in that system in order to make a meaningful distance determination. Using a sample of 8 Galactic open clusters and the GC 47 Tuc, we determine the cluster distances, and hence the RC absolute magnitude in V, I and K, by applying our empirical main sequence fitting method, which utilizes a large sample of local field dwarfs with accurate HIPPARCOS parallaxes. The age and metallicity range of these 9 clusters enable us to make a quantitative assessment of the age and metallicity dependencies of the population corrections predicted by the theoretical models of Girardi & Salaris (2001). We find excellent agreement between the empirical data and the models in all 3 pass-bands, with no statistically significant trends or offsets, thus fully confirming the applicability of the models to single-age, single-metallicity stellar populations. Since, from the models, the population correction is a complicated function of both metallicity and age, if this method is used to derive distances to composite populations, it is essential to have an accurate assessment of the SFR and AMR of the system in question, if errors of several tenths of a magnitude are to be avoided.Comment: 9 pages, 5 figures. MNRAS accepte

A Multiply Imaged Luminous Infrared Galaxy Behind the Bullet Cluster

We present evidence for a Spitzer-selected luminous infrared galaxy (LIRG) behind the Bullet Cluster. The galaxy, originally identified in IRAC photometry as a multiply imaged source, has a spectral energy distribution consistent with a highly extincted (A_V~3.3), strongly star-forming galaxy at z=2.7. Using our strong gravitational lensing model presented in Bradac et al. (2006), we find that the magnifications are 10 to 50 for the three images of the galaxy. The implied infrared luminosity is consistent with the galaxy being a LIRG, with a stellar mass of M_*~2e11 M_Sun and a star formation rate of ~90 M_Sun/yr. With lensed fluxes at 24 microns of 0.58 mJy and 0.39 mJy in the two brightest images, this galaxy presents a unique opportunity for detailed study of an obscured starburst with star fomation rate comparable to that of L* galaxies at z>2.Comment: 9 pages, 5 figures, ApJ, accepted. This version includes information on a third lensed image of the galax

Hybrid governance and the attribution of political responsibility: experimental evidence from the United States

How does the mode of public service delivery affect the attribution of responsibility for public goods? Through a survey experiment on a sample of more than 1,000 Americans, we provide evidence of how the allocation of public goods shapes voters' support for incumbent politicians. We find that voters prefer a mixture of public-private financing and management when it comes to the delivery of infrastructure. However, once performance information is available, the mode of infrastructure delivery no longer influences their voting intention. The successful delivery of these infrastructure projects is what ultimately matters to voters. Moreover, this preference for a mixture of public and private involvement in public service delivery is stronger among citizens with high political knowledge, who are more likely to punish the incumbent for a failed first phase of the public service delivery. These findings deepen our understanding of how hybrid forms of public service delivery are perceived by voters and how performance information affects evaluations of the performance of public services and politicians alike