Context . Long-period transiting exoplanets bridge the gap between the bulk of transit- and Doppler-based exoplanet discoveries, providing key insights into the formation and evolution of planetary ...systems. The wider separation between these planets and their host stars results in the exoplanets typically experiencing less radiation from their host stars; hence, they should maintain more of their original atmospheres, which can be probed during transit via transmission spectroscopy. Although the known population of long-period transiting exoplanets is relatively sparse, surveys performed by the Transiting Exoplanet Survey Satellite (TESS) and the Next Generation Transit Survey (NGTS) are now discovering new exoplanets to fill in this crucial region of the exoplanetary parameter space. Aims . This study aims to characterise a new long-period transiting exoplanet by following up on a single-transit candidate found in the TESS mission. Methods . The TOI-4862 system was monitored using a combination of photometric instruments (TESS, NGTS, and EulerCam) and spectroscopic instruments (CORALIE, FEROS, HARPS, and PFS) in order to determine the period, radius, and mass of the long-period transiting exoplanet NGTS-30 b/TOI-4862 b. These observations were then fitted simultaneously to determine precise values for the properties and orbital parameters of the exoplanet, as well as the refined stellar parameters of the host star. Results . We present the discovery of a long-period ( P = 98.29838 ± 0.00010 day) Jupiter-sized (0.928 ± 0.032 R J ; 0.960 ± 0.056 M J ) planet transiting a 1.1 Gyr old G-type star, one of the youngest warm Jupiters discovered to date. NGTS-30 b/TOI-4862 b has a moderate eccentricity (0.294 −0.010 +0.014 ), meaning that its equilibrium temperature can be expected to vary from 274 −46 +30 K to 500 −84 +55 K over the course of its orbit. Through interior modelling, NGTS-30 b/TOI-4862b was found to have a heavy element mass fraction of 0.23 −0.06 +0.05 and a heavy element enrichment ( Z p / Z ★ ) of 20 −6 +5 , making it metal-enriched compared to its host star. Conclusions . NGTS-30 b/TOI-4862 b is one of the youngest well-characterised long-period exoplanets found to date and will therefore be important in the quest to understanding the formation and evolution of exoplanets across the full range of orbital separations and ages.
Long-period transiting exoplanets bridge the gap between the bulk of transit- and Doppler-based exoplanet discoveries, providing key insights into the formation and evolution of planetary systems. ...The wider separation between these planets and their host stars results in the exoplanets typically experiencing less radiation from their host stars; hence, they should maintain more of their original atmospheres, which can be probed during transit via transmission spectroscopy. Although the known population of long-period transiting exoplanets is relatively sparse, surveys performed by the Transiting Exoplanet Survey Satellite (TESS) and the Next Generation Transit Survey (NGTS) are now discovering new exoplanets to fill in this crucial region of the exoplanetary parameter space. This study presents the detection and characterisation of NGTS-30 b/TOI-4862 b, a new long-period transiting exoplanet detected by following up on a single-transit candidate found in the TESS mission. Through monitoring using a combination of photometric instruments (TESS, NGTS, and EulerCam) and spectroscopic instruments (CORALIE, FEROS, HARPS, and PFS), NGTS-30 b/TOI-4862 b was found to be a long-period (P = 98.29838 day) Jupiter-sized (0.928 RJ; 0.960 MJ) planet transiting a 1.1 Gyr old G-type star. With a moderate eccentricity of 0.294, its equilibrium temperature could be expected to vary from 274 K to 500 K over the course of its orbit. Through interior modelling, NGTS-30 b/TOI-4862 b was found to have a heavy element mass fraction of 0.23 and a heavy element enrichment (Zp/Z_star) of 20, making it metal-enriched compared to its host star. NGTS-30 b/TOI-4862 b is one of the youngest well-characterised long-period exoplanets found to date and will therefore be important in the quest to understanding the formation and evolution of exoplanets across the full range of orbital separations and ages.
This study examines, for the first time in the energy issues literature, the long-run relationship between rare earth prices and the consumption of energy from renewables. The study applies standard ...time series econometric methodologies and monthly data in relevance to regional and income classification groups of countries, spanning the period 2004–2016. The empirical findings indicate the presence of a long-run relationship between these variables, but for certain rare earths and regions. The findings survive a multivariate robustness test, while they are expected to be of substantial importance for the world community, given that a few countries have control of those materials. The importance is lying on the need to establish a global green energy environment.
•The study examines the link between rare earth prices and renewable energy consumption.•It applies cointegration methodologies and monthly data, spanning the period 2004–2016.•The results show the presence of a long-run relationship between them.•They survive a multivariate robustness test.•They should be of substantial importance given that a few countries control them.
•This paper examines the Environmental Kuznet Curve hypothesis for 14 Asian countries.•We focused on how both income and policies in these countries affect the income–emissions relationship.•The GMM ...methodology using panel data is employed in a multivariate framework. Environmental Kuznet Curve hypothesis is confirmed for 14 Asian countries.
The aim of this study is to test the Environmental Kuznet Curve (EKC) hypothesis for 14 Asian countries spanning the period 1990–2011. We focused on how both income and policies in these countries affect the income–emissions (environment) relationship. The GMM methodology using panel data is employed in a multivariate framework to test the EKC hypothesis. The multivariate framework includes: CO2 emissions, GDP per capita, population density, land, industry shares in GDP, and four indicators that measure the quality of institutions. In terms of the presence of an inverted U-shape association between emissions and income per capita, the estimates have the expected signs and are statistically significant, yielding empirical support to the presence of an Environmental Kuznets Curve hypothesis.
The goal of this work is to explore the role of the Covid-19 pandemic event in the course of inflation expectations and their volatility through US inflation swap rates. The findings document that ...inflation expectations and their volatility are positively affected by the Covid-19 pandemic. These results have real activity implications, while close monitoring of inflation expectations could signal inflation expectations un-anchoring risks.
Using data on per capita CO2 emissions and per capita real GDP from fifteen countries, spanning the period 1960–2013, this paper tests the validity of the Environmental Kuznets Curve (EKC) using both ...panel-based and time-series-based methodological approaches of cointegration. Given that the EKC hypothesis postulates an inverted U-shaped relationship between emissions and output, the study tests for cointegration between per capita CO2 emissions, per capita real GDP and the squared values of per capita real GDP. The evidence from panel cointegration methodologies is mixed. This result might arise due to time dependence of cointegrating coefficients. The time-varying cointegration approaches provide strong evidence in favor of time-varying cointegration parameters. Furthermore, based on the quantile cointegration approach, the results indicate that the EKC hypothesis holds in 12 out of the 15 countries. However, even for these three countries, the EKC hypothesis seems to hold at certain quantiles.
•The paper tests for the validity of the Environmental Kuznets Curve (EKC).•It uses data from fifteen countries, spanning the period 1960–2013.•It uses panel, time-series and time-varying approaches of cointegration.•The evidence from panel methods is mixed due to time dependence of coefficients.•The results from time-varying cointegration are in favor of time-varying parameters.
The goal of this study is to analyze the impact of Internet use, employed as a proxy for information and communications technologies (ICTs), on CO
2
emissions. Using a panel of 20 emerging economies ...spanning the period 1990 to 2015, this paper finds that increased Internet access results in lower levels of air pollution. Moreover, panel causality test results highlight a unidirectional causality running from Internet use to CO
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emissions. This result also has crucial policy implications for the governments in emerging markets. For instance, increased investment in the ICT sector could be a plausible channel to reduce air pollution level.
•The environmental convergence hypothesis is examined through the ecological footprint.•The club convergence test is performed.•The results show the presence of divergent clubs.•Common environmental ...policies are questioned.
The ecological footprint has currently become a highly popular environmental performance indicator. It provides the basis for setting goals, identifying options for action, and tracking progress toward stated goals. This paper investigates the convergence of the per capita ecological footprint by employing the annual data for the case of the European Union countries, spanning the period 1961 to 2013. The methodology follows the club clustering approach and the empirical findings document the presence of certain convergent clubs. These empirical results clarify the differences in terms of environmental quality, as well as the awareness strategies the EU members in each club need to follow.
•The paper explores the effect of monetary policy shocks on corporate cash holdings.•Eurozone firms.•The identification approach-shocks decomposition at various horizons.•Shocks have mixed ...effects-previous research was supporting either direction.
This paper explores the effect of ECB monetary policy shocks on eurozone corporate cash holdings. Through the identification approach, we document that shocks have mixed effects, while previous research was supporting either direction.
This study examines the relationship between renewable energy consumption and economic growth for a panel of twenty OECD countries over the period 1985–2005 within a multivariate framework. Given the ...relatively short span of the time series data, a panel cointegration and error correction model is employed to infer the causal relationship. The heterogeneous panel cointegration test reveals a long-run equilibrium relationship between real GDP, renewable energy consumption, real gross fixed capital formation, and the labor force with the respective coefficients positive and statistically significant. The Granger-causality results indicate bidirectional causality between renewable energy consumption and economic growth in both the short- and long-run.
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