| 1. |
- Carleo, Ilaria, et al.
(author)
-
The Multiplanet System TOI-421*
- 2020
-
In: Astronomical Journal. - : American Astronomical Society. - 1538-3881 .- 0004-6256. ; 160:3
-
Journal article (peer-reviewed)abstract
- We report the discovery of a warm Neptune and a hot sub-Neptune transiting TOI-421 (BD-14 1137, TIC 94986319), a bright (V = 9.9) G9 dwarf star in a visual binary system observed by the Transiting Exoplanet Survey Satellite (TESS) space mission in Sectors 5 and 6. We performed ground-based follow-up observations-comprised of Las Cumbres Observatory Global Telescope transit photometry, NIRC2 adaptive optics imaging, and FIbre-fed Echelle Spectrograph, CORALIE, High Accuracy Radial velocity Planet Searcher, High Resolution echelle Spectrometer, and Planet Finder Spectrograph high-precision Doppler measurements-and confirmed the planetary nature of the 16 day transiting candidate announced by the TESS team. We discovered an additional radial velocity signal with a period of five days induced by the presence of a second planet in the system, which we also found to transit its host star. We found that the inner mini-Neptune, TOI-421 b, has an orbital period of P-b = 5.19672 +/- 0.00049 days, a mass of M-b = 7.17 +/- 0.66 M-circle plus, and a radius of R-b = R-circle plus, whereas the outer warm Neptune, TOI-421 c, has a period of P-c = 16.06819 +/- 0.00035 days, a mass of M-c = 16.42(-1.04)(+1.06)M(circle plus), a radius of R-c = 5.09(-0.15)(+0.16)R(circle plus), and a density of rho(c) = 0.685(-0.072)(+0.080) cm(-3). With its characteristics, the outer planet (rho(c) = 0.685(-0.0072)(+0.080) cm(-3)) is placed in the intriguing class of the super-puffy mini-Neptunes. TOI-421 b and TOI-421 c are found to be well-suited for atmospheric characterization. Our atmospheric simulations predict significant Ly alpha transit absorption, due to strong hydrogen escape in both planets, as well as the presence of detectable CH4 in the atmosphere of TOI-421 c if equilibrium chemistry is assumed.
|
|
| 2. |
- Subjak, Jan, et al.
(author)
-
TOI-503: The First Known Brown-dwarf Am-star Binary from the TESS Mission
- 2020
-
In: Astronomical Journal. - : American Astronomical Society. - 1538-3881 .- 0004-6256. ; 159:4
-
Journal article (peer-reviewed)abstract
- We report the discovery of an intermediate-mass transiting brown dwarf (BD), TOI-503b, from the TESS mission. TOI-503b is the first BD discovered by TESS, and it has circular orbit around a metallic-line A-type star with a period of P.=.3.6772.+/-.0.0001 days. The light curve from TESS indicates that TOI-503b transits its host star in a grazing manner, which limits the precision with which we measure the BD's radius ( = R 1.34+ R b 0.150.26 J). We obtained highresolution spectroscopic observations with the FIES, Ondr.ejov, PARAS, Tautenburg, and TRES spectrographs, and measured the mass of TOI-503b to be Mb.=.53.7.+/-.1.2 MJ. The host star has a mass of Ma.=.1.80.+/-.0.06Me, a radius of Ra.=.1.70.+/-.0.05Re, an effective temperature of Teff.=.7650.+/-.160 K, and a relatively high metallicity of 0.61.+/-.0.07 dex. We used stellar isochrones to derive the age of the system to be 180 Myr, which places its age between that of RIK 72b (a 10 Myr old BD in the Upper Scorpius stellar association) and AD 3116b (a 600 Myr old BD in the Praesepe cluster). Given the difficulty in measuring the tidal interactions between BDs and their host stars, we cannot precisely say whether this BD formed in situ or has had its orbit circularized by its host star over the relatively short age of the system. Instead, we offer an examination of plausible values for the tidal quality factor for the star and BD. TOI-503b joins a growing number of known short-period, intermediate-mass BDs orbiting mainsequence stars, and is the second such BD known to transit an A star, after HATS-70b. With the growth in the population in this regime, the driest region in the BD desert (35-55MJ sin i) is reforesting.
|
|
| 3. |
- Babor, Thomas F., et al.
(author)
-
Alcohol : No Ordinary Commodity - a summary of the third edition
- 2022
-
In: Addiction. - : NLM (Medline). - 0965-2140 .- 1360-0443. ; 117:12, s. 3024-3036
-
Journal article (peer-reviewed)abstract
- Background and Aims: This article summarizes the findings and conclusions of the third edition of Alcohol: No Ordinary Commodity. The latest revision of this book is part of a series of monographs designed to provide a critical review of the scientific evidence related to alcohol control policy from a public health perspective.Design: A narrative summary of the contents of the book according to five major issues.Findings: An extensive amount of epidemiological evidence shows that alcohol is a major contributor to the global burden of disease, disability and death in high-, middle- and low-income countries. Trends in alcohol products and marketing are described, indicating that a large part of the global industry has been consolidated into a small number of transnational corporations that are expanding their operations in Asia, Africa and Latin America. The main part of the book is devoted to a review of strategies and interventions designed to prevent or minimize alcohol-related harm. Overall, the most effective strategies to protect public health are taxation that decreases affordability and restrictions on the physical availability of alcohol. A total ban on alcohol marketing is also an effective strategy to reduce consumption. In addition, drink-driving counter-measures, brief interventions with at-risk drinkers and treatment of drinkers with alcohol dependence are effective in preventing harm in high-risk contexts and groups of hazardous drinkers.Conclusion: Alcohol policy is often the product of competing interests, values and ideologies, with the evidence suggesting that the conflicting interests between profit and health mean that working in partnership with the alcohol industry is likely to lead to ineffective policy. Opportunities for implementation of evidence-based alcohol policies that better serve the public good are clearer than ever before as a result of accumulating knowledge on which strategies work best.
|
|
| 4. |
- Babor, Thomas F., et al.
(author)
-
Alcohol : No Ordinary Commodity - A Summary of the Third Edition
- 2023
-
In: SUCHT. - 0939-5911 .- 1664-2856. ; 69:4, s. 147-162
-
Journal article (peer-reviewed)abstract
- Background and Aims: This article summarizes the findings and conclusions of the third edition of Alcohol: No Ordinary Commodity. The latest revision of this book is part of a series of monographs designed to provide a critical review of the scientific evidence related to alcohol control policy from a public health perspective. Design: A narrative summary of the contents of the book according to five major issues. Findings: An extensive amount of epidemiological evidence shows that alcohol is a major contributor to the global burden of disease, disability and death in high-, middle- and low-income countries. Trends in alcohol products and marketing are described, indicating that a large part of the global industry has been consolidated into a small number of transnational corporations that are expanding their operations in Asia, Africa and Latin America. The main part of the book is devoted to a review of strategies and interventions designed to prevent or minimize alcohol-related harm. Overall, the most effective strategies to protect public health are taxation that decreases affordability and restrictions on the physical availability of alcohol. A total ban on alcohol marketing is also an effective strategy to reduce consumption. In addition, drink-driving counter-measures, brief interventions with at-risk drinkers and treatment of drinkers with alcohol dependence are effective in preventing harm in high-risk contexts and groups of hazardous drinkers. Conclusion: Alcohol policy is often the product of competing interests, values and ideologies, with the evidence suggesting that the conflicting interests between profit and health mean that working in partnership with the alcohol industry is likely to lead to ineffective policy. Opportunities for implementation of evidence-based alcohol policies that better serve the public good are clearer than ever before as a result of accumulating knowledge on which strategies work best.
|
|
| 5. |
- Callinan, Sarah, et al.
(author)
-
Age-based differences in quantity and frequency of consumption when screening for harmful alcohol use
- 2022
-
In: Addiction. - : Wiley. - 0965-2140 .- 1360-0443. ; 117:9, s. 2431-2437
-
Journal article (peer-reviewed)abstract
- Background and aims: Survey questions on usual quantity and frequency of alcohol consumption are regularly used in screening tools to identify drinkers requiring intervention. The aim of this study was to measure age-based differences in quantity and frequency of alcohol consumption on the Alcohol Use Disorders Identification Test (AUDIT) and how this relates to the prediction of harmful or dependent drinking.Design: Cross-sectional survey.Setting: Australia.Participants: Data were taken from 17 399 respondents who reported any alcohol consumption in the last year and were aged 18 and over from the 2016 National Drug Strategy Household Survey, a broadly representative cross-sectional survey on substance use.Measurement: Respondents were asked about their frequency of consumption, usual quantity per occasion and the other items of the AUDIT.Findings: In older drinkers, quantity per occasion [β = 0.53, 95% confidence interval (CI) = 0.43, 0.64 in 43–47-year-olds as an example] was a stronger predictor of dependence than frequency per occasion (β = 0.24, 95% CI = 0.17, 0.31). In younger drinkers the reverse was true, with frequency a stronger predictor (β = 0.54, 95% CI = 0.39, 0.69 in 23–27-year-olds) than quantity (β = 0.26, 95% CI = 0.18, 0.34 in 23–27-year-olds). Frequency of consumption was not a significant predictor of dependence in respondents aged 73 years and over (β = −0.03, 95% CI = −0.08, 0.02). Similar patterns were found when predicting harmful drinking. Despite this, as frequency of consumption increased steadily with age, the question on frequency was responsible for at least 65% of AUDIT scores in drinkers aged 53 years and over.Conclusions: In younger drinkers, frequent drinking is more strongly linked to dependence and harmful drinking subscale scores on the Alcohol Use Disorders Identification Test (AUDIT) than quantity per occasion, yet quantity per occasion has a stronger influence on the overall AUDIT score in this group. In older drinkers, frequency of consumption is not always a significant predictor of the AUDIT dependence subscale and is a weak predictor of the harmful drinking subscale.
|
|
| 6. |
- Callinan, Sarah, et al.
(author)
-
Purchasing, consumption, demographic and socioeconomic variables associated with shifts in alcohol consumption during the COVID-19 pandemic
- 2021
-
In: Drug and Alcohol Review. - : Wiley. - 0959-5236 .- 1465-3362. ; 45, s. 24A-24A
-
Journal article (peer-reviewed)abstract
- Introduction and Aims: Restrictions introduced to reduce the spread of COVID-19 have had major impacts on the living circumstances of Australians. This paper aims to provide insight into shifts in alcohol consumption and associated factors during the epidemic. Design and Methods: A cross-sectional convenience sample of 2307 Australians aged 18 and over who drank at least monthly was recruited through social media. Respondents were asked about their alcohol consumption and purchasing in 2019 prior to the epidemic plus similar questions about their experiences in the month prior to being surveyed between 29 April and 16 May 2020. Results: Reports of average consumption before (3.53 drinks per day [3.36, 3.71 95% confidence interval]) and during (3.52 [3.34, 3.69]) the pandemic were stable. However, young men and those who drank more outside the home in 2019 reported decreased consumption during the pandemic, and people with high levels of stress and those who bulk-bought alcohol when restrictions were announced reported an increase in consumption relative to those who did not. Discussion and Conclusions: A reported increase in consumption among those experiencing more stress suggests that some people may have been drinking to cope during the epidemic. Conversely, the reported decrease in consumption among those who drank more outside of their home in 2019 suggests that closing all on-trade sales did not result in complete substitution of on-premise drinking with home drinking in this group. Monitoring of relevant subgroups to assess long-term changes in consumption in the aftermath of the epidemic is recommended.
|
|
| 7. |
- Diaz, Matias R., et al.
(author)
-
TOI-132 b: A short-period planet in the Neptune desert transiting a V=11.3 G-type star
- 2020
-
In: Monthly Notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 493:1, s. 973-985
-
Journal article (peer-reviewed)abstract
- The Neptune desert is a feature seen in the radius-period plane, whereby a notable dearth of short period, Neptune-like planets is found. Here, we report the Transiting Exoplanet Survey Satellite (TESS) discovery of a new short-period planet in the Neptune desert, orbiting the G-type dwarf TYC 8003-1117-1 (TOI-132). TESS photometry shows transit-like dips at the level of similar to 1400 ppm occurring every similar to 2.11 d. High-precision radial velocity follow-up with High Accuracy Radial Velocity Planet Searcher confirmed the planetary nature of the transit signal and provided a semi-amplitude radial velocity variation of 11.38(-0.85)(+0.84) m s(-1), which, when combined with the stellar mass of 0.97 +/- 0.06 M-circle dot, provides a planetary mass of 22.40(-1.92)(+1.90) M-circle plus. Modelling the TESS light curve returns a planet radius of 3.42(-0.14)(+0.13) R-circle plus , and therefore the planet bulk density is found to be 3.08(-0.46)(+0.44) g cm(-3). Planet structure models suggest that the bulk of the planet mass is in the form of a rocky core, with an atmospheric mass fraction of 4.3(-2.3)(+1.2) percent. TOI-132 b is a TESS Level 1 Science Requirement candidate, and therefore priority follow-up will allow the search for additional planets in the system, whilst helping to constrain low-mass planet formation and evolution models, particularly valuable for better understanding of the Neptune desert.
|
|
| 8. |
- Fridlund, Malcolm, 1952, et al.
(author)
-
Planets observed with CHEOPS: Two super-Earths orbiting the red dwarf star TOI-776
- 2024
-
In: Astronomy and Astrophysics. - 0004-6361 .- 1432-0746. ; 684
-
Journal article (peer-reviewed)abstract
- Context. M-dwarf stars are the most common of potential exoplanet host stars in the Galaxy. It is therefore very important to understand planetary systems orbiting such stars and to determine the physical parameters of such planets with high precision. Also with the launch of the James Webb Space Telescope (JWST) the observation of atmospheric parameters of planets orbiting these stars has begun. It is therefore required to determine properties of potential targets. Aims. Two planets around the red dwarf TOI-776 were detected by TESS. The objective of our study was to use transit observations obtained by the CHEOPS space mission to improve the current precision of the planetary radii, as well as additional radial velocity (RV) data in order to improve mass estimates of the two planets. Using these quantities, we wanted to derive the bulk densities of those planets, improving the precision in earlier results, and use this information to put them in context of other exoplanetary systems involving very low mass stars. Methods. Utilizing new transit data from the CHEOPS satellite and its photometric telescope, we obtained very high precision planetary transit measurements. Interpretation of these provides updated planetary radii, along with other system parameters. A concurrent ESO large observing program using the high precision spectrograph HARPS has doubled the available radial velocity data. Calculating the power spectrum of a number of stellar activity indices we update the previously estimated stellar rotation period to a lower value. Results. The CHEOPS data provide precise transit depths of 909 and 1177 ppm translating into radii of Rb = 1.798-0.077+0.078 R⊕ and Rc = 2.047-0.078+0.081 R⊕, respectively. Our interpretation of the radial velocities and activity indicator time series data estimates a stellar rotation period for this early M dwarf of ~21.1 days. A further multi-dimensional Gaussian process approach confirm this new estimate. By performing a Skew-Normal (SN) fit onto the Cross Correlation Functions we extracted the RV data and the activity indicators to estimate the planetary masses, obtaining Mb = 5.0-1.6+1.6 M⊕ and Mc = 6.9-2.5+2.6 M⊕. Conclusions. We improve the precision in planetary radius for TOI-776 b and c by a factor of more than two. Our data and modelling give us parameters of both bodies consistent with mini-Neptunes, albeit with a relatively high density. The stellar activity of TOI-776 is found to have increased by a factor larger than 2 since the last set of observations.
|
|
| 9. |
- Harakawa, Hiroki, et al.
(author)
-
A super-Earth orbiting near the inner edge of the habitable zone around the M4.5 dwarf Ross 508
- 2022
-
In: Publications of the Astronomical Society of Japan. - : Oxford University Press (OUP). - 0004-6264 .- 2053-051X. ; 74:4, s. 904-922
-
Journal article (peer-reviewed)abstract
- We report the near-infrared radial velocity (RV) discovery of a super-Earth planet on a 10.77 d orbit around the M4.5 dwarf Ross 508 (Jmag = 9.1). Using precision RVs from the Subaru Telescope IRD (InfraRed Doppler) instrument, we derive a semi-amplitude of 3.92ms−1, corresponding to a planet with a minimum mass msini=4.00M⊕. We find no evidence of significant signals at the detected period in spectroscopic stellar activity indicators or MEarth photometry. The planet, Ross 508 b, has a semi-major axis of 0.05366au. This gives an orbit-averaged insolation of ≈1.4 times the Earth’s value, placing Ross 508 b near the inner edge of its star’s habitable zone. We have explored the possibility that the planet has a high eccentricity and its host is accompanied by an additional unconfirmed companion on a wide orbit. Our discovery demonstrates that the near-infrared RV search can play a crucial role in finding a low-mass planet around cool M dwarfs like Ross 508.
|
|
| 10. |
- Hori, Yasunori, et al.
(author)
-
The Discovery and Follow-up of Four Transiting Short-period Sub-Neptunes Orbiting M Dwarfs
- 2024
-
In: Astronomical Journal. - 1538-3881 .- 0004-6256. ; 167:6
-
Journal article (peer-reviewed)abstract
- Sub-Neptunes with radii of 2-3 R ⊕ are intermediate in size between rocky planets and Neptune-sized planets. The orbital properties and bulk compositions of transiting sub-Neptunes provide clues to the formation and evolution of close-in small planets. In this paper, we present the discovery and follow-up of four sub-Neptunes orbiting M dwarfs (TOI-782, TOI-1448, TOI-2120, and TOI-2406), three of which were newly validated by ground-based follow-up observations and statistical analyses. TOI-782 b, TOI-1448 b, TOI-2120 b, and TOI-2406 b have radii of R p = 2.740 − 0.079 + 0.082 R ⊕ , 2.769 − 0.068 + 0.073 R ⊕ , 2.120 ± 0.067 R ⊕, and 2.830 − 0.066 + 0.068 R ⊕ and orbital periods of P = 8.02, 8.11, 5.80, and 3.08 days, respectively. Doppler monitoring with the Subaru/InfraRed Doppler instrument led to 2σ upper limits on the masses of <19.1 M ⊕, <19.5 M ⊕, <6.8 M ⊕, and <15.6 M ⊕ for TOI-782 b, TOI-1448 b, TOI-2120 b, and TOI-2406 b, respectively. The mass-radius relationship of these four sub-Neptunes testifies to the existence of volatile material in their interiors. These four sub-Neptunes, which are located above the so-called “radius valley,” are likely to retain a significant atmosphere and/or an icy mantle on the core, such as a water world. We find that at least three of the four sub-Neptunes (TOI-782 b, TOI-2120 b, and TOI-2406 b), orbiting M dwarfs older than 1 Gyr, are likely to have eccentricities of e ∼ 0.2-0.3. The fact that tidal circularization of their orbits is not achieved over 1 Gyr suggests inefficient tidal dissipation in their interiors.
|
|
