10 research outputs found
A pragmatic approach to evaluate alternative indicators to GDP
The serious economic crisis broken out in 2008 highly stressed the limitations of GDP used as a well-being indicator and as a predictive tool for economy. This induced the need to identify new indicators able to link the economic prosperity of a country to aspects of sustainable development and externalities, both positive and negative, in the long run. The aim of this paper is to introduce a structured approach which supports the choice or the construction of alternative indicators to GDP. The starting point is the definition of what a well-being indicator actually should represent according to the Recommendations of the Stiglitz-Sen-Fitoussi Report on the measurement of economic performance and social progress. Then the paper introduces a systematic procedure for the analysis of well-being indicators. The different phases of this procedure entail the checking of indicators technical properties and their effect on the representational efficacy. Finally, some of the most representative well-being indicators drawn from the literature are compared and a detailed application example is propose
Planet Hunters Tess I: TOI 813, a subgiant hosting a transiting Saturn-sized planet on an 84-day orbit
We report on the discovery and validation of TOI 813 b (TIC55525572b), a transiting exoplanet identified by citizen scientists in data from NASA's Transiting Exoplanet Survey Satellite (TESS) and the first planet discovered by the Planet Hunters TESS project. The host star is a bright (V = 10.3 mag) subgiant (R* = 1.94 Râ, Mâ = 1.32 Mâ). It was observed almost continuously by TESS during its first year of operations, during which time four individual transit events were detected. The candidate passed all the standard light curve-based vetting checks, and ground-based follow-up spectroscopy and speckle imaging enabled us to place an upper limit of 2 MJup (99 per cent confidence) on the mass of the companion, and to statistically validate its planetary nature. Detailed modelling of the transits yields a period of 83.8911+0.0027-0.0031 d, a planet radius of 6.71 ± 0.38 Râ and a semimajor axis of 0.423+0031-0.037 AU. The planet's orbital period combined with the evolved nature of the host star places this object in a relatively underexplored region of parameter space. We estimate that TOI 813 b induces a reflex motion in its host star with a semi-amplitude of âŒ6 m sâ1, making this a promising system to measure the mass of a relatively long-period transiting planet
TOI-1338: TESS' First Transiting Circumbinary Planet
We report the detection of the first circumbinary planet (CBP) found by Transiting Exoplanet Survey Satellite (TESS). The target, a known eclipsing binary, was observed in sectors 1 through 12 at 30 minute cadence and in sectors 4 through 12 at 2 minute cadence. It consists of two stars with masses of 1.1 M o˙ and 0.3 M o˙ on a slightly eccentric (0.16), 14.6 day orbit, producing prominent primary eclipses and shallow secondary eclipses. The planet has a radius of âŒ6.9 R â and was observed to make three transits across the primary star of roughly equal depths (âŒ0.2%) but different durations-a common signature of transiting CBPs. Its orbit is nearly circular (e â 0.09) with an orbital period of 95.2 days. The orbital planes of the binary and the planet are aligned to within âŒ1°. To obtain a complete solution for the system, we combined the TESS photometry with existing ground-based radial-velocity observations in a numerical photometric-dynamical model. The system demonstrates the discovery potential of TESS for CBPs and provides further understanding of the formation and evolution of planets orbiting close binary stars
Planet Hunters TESS I: TOI 813, a subgiant hosting a transiting Saturn-sized planet on an 84-day orbit
We report on the discovery and validation of TOI 813b (TIC 55525572 b), a
transiting exoplanet identified by citizen scientists in data from NASA's
Transiting Exoplanet Survey Satellite (TESS) and the first planet discovered by
the Planet Hunters TESS project. The host star is a bright (V = 10.3 mag)
subgiant (, ). It was observed
almost continuously by TESS during its first year of operations, during which
time four individual transit events were detected. The candidate passed all the
standard light curve-based vetting checks, and ground-based follow-up
spectroscopy and speckle imaging enabled us to place an upper limit of (99 % confidence) on the mass of the companion, and to statistically
validate its planetary nature. Detailed modelling of the transits yields a
period of days, a planet radius of , and a semi major axis of AU. The planet's orbital period combined with the evolved nature of the host
star places this object in a relatively under-explored region of parameter
space. We estimate that TOI-813b induces a reflex motion in its host star with
a semi-amplitude of ms, making this system a promising target to
measure the mass of a relatively long-period transiting planet.Comment: Accepted for publication in MNRAS (16 pages, 10 figures, 3 tables