129 research outputs found

    Critical engagement

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    This book represents the first interdisciplinary study of how memory has driven and challenged the political transition of Irish republicanism from armed conflict to constitutional politics through endorsing policing and the rule of law in the North of Ireland. Locating itself within memory studies, critical criminology and transitional justice, this book uses original interviews with political activists, community workers and former combatants from across the spectrum of modern Irish republicanism to draw out how the past frames internal tensions within the Irish republican constituency as those traditionally opposed to state policing structures opt to buy into them as part of a wider transitional process in post-conflict Northern Ireland. The book critiques the challenges of making peace with the enemy against a backdrop of communal narratives and memories of historic injustice, counterinsurgency policing and human rights abuse that do not simply disappear when war turns to peace. Through a rich empirical basis the book offers an insight into these challenges from the perspective of those who were, and remain, in the thick of the Irish republican debate on policing. In doing so it provides an acute insight into the role that individual and collective memory plays in reshaping ideological outlooks, understanding processes of political transition, contextualising ‘moving on’ processes with former enemies and conditioning views of post-conflict police reform

    Hydroxyl as a Tracer of H2 in the Envelope of MBM40

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    We observed 51 positions in the OH 1667 MHz main line transitions in the translucent, high latitude cloud MBM40. We detected OH emission in 8 out of 8 positions in the molecular core of the cloud and 24 out of 43 in the surrounding, lower extinction envelope and periphery of the cloud. Using a linear relationship between the integrated OH line intensity and E(B-V), we estimate the mass in the core, the envelope, and the periphery of the cloud to be 4, 8, and 5 solar masses. As much as a third of the total cloud mass may be found in the in the periphery (E(B-V) << 0.12 mag) and about a half in the envelope (0.12 ≀\le E(B-V) ≀\le 0.17 mag). If these results are applicable to other translucent clouds the OH 1667 MHz line is an excellent tracer of gas in very low extinction regions and high-sensitivity mapping of the envelopes of molecular clouds may reveal the presence of significant quantities of molecular mass.Comment: 26 pages, 3 figures, and 5 table

    TOI-150: A transiting hot Jupiter in the TESS southern CVZ

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    We report the detection of a hot Jupiter ($M_{p}=1.75_{-0.17}^{+0.14}\ M_{J},, R_{p}=1.38\pm0.04\ R_{J})orbitingamiddle−agedstar() orbiting a middle-aged star (\log g=4.152^{+0.030}_{-0.043})intheTransitingExoplanetSurveySatellite(TESS)southerncontinuousviewingzone() in the Transiting Exoplanet Survey Satellite (TESS) southern continuous viewing zone (\beta=-79.59^{\circ}$). We confirm the planetary nature of the candidate TOI-150.01 using radial velocity observations from the APOGEE-2 South spectrograph and the Carnegie Planet Finder Spectrograph, ground-based photometric observations from the robotic Three-hundred MilliMeter Telescope at Las Campanas Observatory, and Gaia distance estimates. Large-scale spectroscopic surveys, such as APOGEE/APOGEE-2, now have sufficient radial velocity precision to directly confirm the signature of giant exoplanets, making such data sets valuable tools in the TESS era. Continual monitoring of TOI-150 by TESS can reveal additional planets and subsequent observations can provide insights into planetary system architectures involving a hot Jupiter around a star about halfway through its main-sequence life.Comment: 13 pages, 3 figures, 2 tables, accepted to ApJ

    Kepler-503b: An Object at the Hydrogen Burning Mass Limit Orbiting a Subgiant Star

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    Using spectroscopic radial velocities with the APOGEE instrument and Gaia distance estimates, we demonstrate that Kepler-503b, currently considered a validated Kepler planet, is in fact a brown-dwarf/low-mass star in a nearly circular 7.2-day orbit around a subgiant star. Using a mass estimate for the primary star derived from stellar models, we derive a companion mass and radius of 0.075±0.003 M⊙0.075\pm0.003 \ M_{\odot} (78.6±3.1 MJup78.6\pm3.1 \ M_{Jup}) and 0.099−0.004+0.006 R⊙0.099^{+0.006}_{-0.004}\ R_{\odot} (0.96−0.04+0.06 RJup0.96^{+0.06}_{-0.04}\ R_{Jup}), respectively. Assuming the system is coeval, the evolutionary state of the primary indicates the age is ∌6.7\sim6.7 Gyr. Kepler-503b sits right at the hydrogen burning mass limit, straddling the boundary between brown dwarfs and very low-mass stars. More precise radial velocities and secondary eclipse spectroscopy with James Webb Space Telescope will provide improved measurements of the physical parameters and age of this important system to better constrain and understand the physics of these objects and their spectra. This system emphasizes the value of radial velocity observations to distinguish a genuine planet from astrophysical false positives, and is the first result from the SDSS-IV monitoring of Kepler planet candidates with the multi-object APOGEE instrument.Comment: Accepted for publication in ApJL, 12 pages, 3 figures, 2 table

    The Ninth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the SDSS-III Baryon Oscillation Spectroscopic Survey

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    The Sloan Digital Sky Survey III (SDSS-III) presents the first spectroscopic data from the Baryon Oscillation Spectroscopic Survey (BOSS). This ninth data release (DR9) of the SDSS project includes 535,995 new galaxy spectra (median z=0.52), 102,100 new quasar spectra (median z=2.32), and 90,897 new stellar spectra, along with the data presented in previous data releases. These spectra were obtained with the new BOSS spectrograph and were taken between 2009 December and 2011 July. In addition, the stellar parameters pipeline, which determines radial velocities, surface temperatures, surface gravities, and metallicities of stars, has been updated and refined with improvements in temperature estimates for stars with T_eff<5000 K and in metallicity estimates for stars with [Fe/H]>-0.5. DR9 includes new stellar parameters for all stars presented in DR8, including stars from SDSS-I and II, as well as those observed as part of the SDSS-III Sloan Extension for Galactic Understanding and Exploration-2 (SEGUE-2). The astrometry error introduced in the DR8 imaging catalogs has been corrected in the DR9 data products. The next data release for SDSS-III will be in Summer 2013, which will present the first data from the Apache Point Observatory Galactic Evolution Experiment (APOGEE) along with another year of data from BOSS, followed by the final SDSS-III data release in December 2014.Comment: 9 figures; 2 tables. Submitted to ApJS. DR9 is available at http://www.sdss3.org/dr

    The Fourteenth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the extended Baryon Oscillation Spectroscopic Survey and from the second phase of the Apache Point Observatory Galactic Evolution Experiment

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    The fourth generation of the Sloan Digital Sky Survey (SDSS-IV) has been in operation since July 2014. This paper describes the second data release from this phase, and the fourteenth from SDSS overall (making this, Data Release Fourteen or DR14). This release makes public data taken by SDSS-IV in its first two years of operation (July 2014-2016). Like all previous SDSS releases, DR14 is cumulative, including the most recent reductions and calibrations of all data taken by SDSS since the first phase began operations in 2000. New in DR14 is the first public release of data from the extended Baryon Oscillation Spectroscopic Survey (eBOSS); the first data from the second phase of the Apache Point Observatory (APO) Galactic Evolution Experiment (APOGEE-2), including stellar parameter estimates from an innovative data driven machine learning algorithm known as "The Cannon"; and almost twice as many data cubes from the Mapping Nearby Galaxies at APO (MaNGA) survey as were in the previous release (N = 2812 in total). This paper describes the location and format of the publicly available data from SDSS-IV surveys. We provide references to the important technical papers describing how these data have been taken (both targeting and observation details) and processed for scientific use. The SDSS website (www.sdss.org) has been updated for this release, and provides links to data downloads, as well as tutorials and examples of data use. SDSS-IV is planning to continue to collect astronomical data until 2020, and will be followed by SDSS-V.Comment: SDSS-IV collaboration alphabetical author data release paper. DR14 happened on 31st July 2017. 19 pages, 5 figures. Accepted by ApJS on 28th Nov 2017 (this is the "post-print" and "post-proofs" version; minor corrections only from v1, and most of errors found in proofs corrected

    Light meson spectroscopy from Dalitz plot analyses of ηc decays to η0 K+K− , η0 π + π − , and ηπ + π − produced in two-photon interactions

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    We study the processes γγ→ηc→ηâ€ČK+K−, ηâ€Čπ+π−, and ηπ+π− using a data sample of 519  fb−1 recorded with the BABAR detector operating at the SLAC PEP-II asymmetric-energy e+e− collider at center-of-mass energies at and near the ΄(nS) (n=2, 3, 4) resonances. This is the first observation of the decay ηc→ηâ€ČK+K− and we measure the branching fraction Γ(ηc→ηâ€ČK+K−)/(Γ(ηc→ηâ€Čπ+π−)=0.644±0.039stat±0.032sys. Significant interference is observed between γγ→ηc→ηπ+π− and the nonresonant two-photon process ÎłÎłâ†’Î·Ï€+π−. A Dalitz plot analysis is performed of ηc decays to ηâ€ČK+K−, ηâ€Čπ+π−, and ηπ+π−. Combined with our previous analysis of ηc→KÂŻKπ, we measure the K∗0(1430) parameters and the ratio between its ηâ€ČK and πK couplings. The decay ηc→ηâ€Čπ+π− is dominated by the f0(2100) resonance, also observed in J/ψ radiative decays. A new a0(1700)→ηπ resonance is observed in the ηc→ηπ+π− channel. We also compare ηc decays to η and ηâ€Č final states in association with scalar mesons as they relate to the identification of the scalar glueball.publishedVersio

    Search for rare or forbidden decays of the D0 meson

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    We present a search for nine lepton-number-violating and three lepton-flavor-violating neutral charm decays of the type D0→h'−h−ℓ'+ℓ+ and D0→h'−h+ℓ'±ℓ∓, where h and hâ€Č represent a K or π meson and ℓ and ℓâ€Č an electron or muon. The analysis is based on 468 fb−1 of e+e− annihilation data collected at or close to the ΄(4S) resonance with the BABAR detector at the SLAC National Accelerator Laboratory. No significant signal is observed for any of the twelve modes, and we establish 90% confidence level upper limits on the branching fractions in the range (1.0–30.6)×10−7. The limits are between 1 and 3 orders of magnitude more stringent than previous measurements.publishedVersio
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