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Precise characterisation of HD 15337 with CHEOPS : a laboratory for planet formation and evolution
Get PDFFunding: CHEOPS is an ESA mission in partnership with Switzerland with important contributions to the payload and the ground segment from Austria, Belgium, France, Germany, Hungary, Italy, Portugal, Spain, Sweden, and the United Kingdom. The CHEOPS Consortium would like to gratefully acknowledge the support received by all the agencies, offices, universities, and industries involved. Their flexibility and willingness to explore new approaches were essential to the success of this mission. This work was supported by FCT – Fundação para a Ciência e a Tecnologia through national funds by these grants: UIDB/04434/2020, UIDP/04434/2020, 2022.06962. PTDC, 2022.04416.PTDC. N.M.R. acknowledges support from FCT through grant DFA/BD/5472/2020. O.D.S.D. is supported in the form of work contract (DL 57/2016/CP1364/CT0004) funded by national funds through FCT. S.C.C.B. acknowledges support from FCT through FCT contracts nr. IF/01312/2014/CP1215/CT0004. D.G. gratefully acknowledges financial support from the CRT foundation under Grant No. 2018.2323 “Gaseous or rocky? Unveiling the nature of small worlds”. J.A.Eg. and Y.Al. acknowledge support from the Swiss National Science Foundation (SNSF) under grant 200020_192038. LMS gratefully acknowledges financial support from the CRT foundation under Grant No. 2018.2323 “Gaseous or rocky? Unveiling the nature of small worlds”. This work has been carried out within the framework of the NCCR PlanetS supported by the Swiss National Science Foundation under grants 51NF40_182901 and 51NF40_205606. T.Wi. and A.C.Ca. acknowledge support from STFC consolidated grant numbers ST/R000824/1 and ST/V000861/1, and UKSA grant number ST/R003203/1. The Belgian participation to CHEOPS has been supported by the Belgian Federal Science Policy Office (BELSPO) in the framework of the PRODEX Program, and by the University of Liège through an ARC grant for Concerted Research Actions financed by the Wallonia-Brussels Federation. L.D. is an F.R.S.-FNRS Postdoctoral Researcher. NCSa acknowledges funding by the European Union (ERC, FIERCE, 101052347). Views and opinions expressed are however those of the author(s) only and do not necessarily reflect those of the European Union or the European Research Council. Neither the European Union nor the granting authority can be held responsible for them. S.G.S. acknowledges support from FCT through FCT contract nr. CEECIND/00826/2018 and POPH/FSE (EC). V.A. is supported by FCT through national funds by the following grant: 2022.06962.PTDC (http://doi.org/ 10.54499/2022.06962.PTDC). RAl, DBa, EPa, and IRi acknowledge financial support from the Agencia Estatal de Investigación of the Ministerio de Ciencia e Innovación MCIN/AEI/10.13039/501100011033 and the ERDF “A way of making Europe” through projects PID2019-107061GB-C61, PID2019- 107061GB-C66, PID2021-125627OB-C31, and PID2021-125627OB-C32, from the Centre of Excellence “Severo Ochoa” award to the Instituto de Astrofísica de Canarias (CEX2019-000920-S), from the Centre of Excellence “María de Maeztu” award to the Institut de Ciències de l’Espai (CEX2020-001058-M), and from the Generalitat de Catalunya/CERCA programme. X.B., S.C., D.G., A282, page 12 of 16 Rosário, N. M., et al.: A&A, 686, A282 (2024) M.F. and J.L. acknowledge their role as ESA-appointed CHEOPS science team members. L.Bo., V.Na., I.Pa., G.Pi., R.Ra., and G.Sc. acknowledge support from CHEOPS ASI-INAF agreement no. 2019-29-HH.0. P.E.C. is funded by the Austrian Science Fund (FWF) Erwin Schroedinger Fellowship, program J4595-N. ABr was supported by the SNSA. This project was supported by the CNES. B.-O.D. acknowledges support from the Swiss State Secretariat for Education, Research and Innovation (SERI) under contract number MB22.00046. This project has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (project FOUR ACES, grant agreement no. 724427). It has also been carried out in the frame of the National Centre for Competence in Research PlanetS supported by the Swiss National Science Foundation (SNSF). DE acknowledges financial support from the Swiss National Science Foundation for project 200021_200726. MF and CMP gratefully acknowledge the support of the Swedish National Space Agency (DNR 65/19, 174/18). M.G. is an F.R.S.-FNRS Senior Research Associate. MNG is the ESA CHEOPS Project Scientist and Mission Representative, and as such also responsible for the Guest Observers (GO) Programme. MNG does not relay proprietary information between the GO and Guaranteed Time Observation (GTO) Programmes, and does not decide on the definition and target selection of the GTO Programme. CHe acknowledges support from the European Union H2020-MSCA-ITN-2019 under Grant Agreement no. 860470 (CHAMELEON). SH gratefully acknowledges CNES funding through the grant 837319. KGI is the ESA CHEOPS Project Scientist and is responsible for the ESA CHEOPS Guest Observers Programme. She does not participate in, or contribute to, the definition of the Guaranteed Time Programme of the CHEOPS mission through which observations described in this paper have been taken, nor to any aspect of target selection for the programme. K.W.F.L. was supported by Deutsche Forschungsgemeinschaft grants RA714/14-1 within the DFG Schwerpunkt SPP 1992, Exploring the Diversity of Extrasolar Planets. This work was granted access to the HPC resources of MesoPSL financed by the Région Ile de France and the project Equip@Meso (reference ANR-10-EQPX29-01) of the programme Investissements d’Avenir supervised by the Agence Nationale pour la Recherche. M.L. acknowledges support of the Swiss National Science Foundation under grant number PCEFP2_194576. P.M. acknowledges support from STFC research grant number ST/M001040/1. This work was also partially supported by a grant from the Simons Foundation (PI Queloz, grant number 327127). GyMSz acknowledges the support of the Hungarian National Research, Development and Innovation Office (NKFIH) grant K-125015, a PRODEX Experiment Agreement No. 4000137122, the Lendület LP2018-7/2021 grant of the Hungarian Academy of Science and the support of the city of Szombathely. V.V.G. is an F.R.S-FNRS Research Associate. NAW acknowledges UKSA grant ST/R004838/1. AN and JV acknowledge support from the Swiss National Science Foundation (SNSF) under grant PZ00P2_208945.Context . The HD 15337 (TIC 120896927, TOI-402) system was observed by the Transiting Exoplanet Survey Satellite (TESS), revealing the presence of two short-period planets situated on opposite sides of the radius gap. This offers an excellent opportunity to study theories of formation and evolution, as well as to investigate internal composition and atmospheric evaporation. Aims . We aim to constrain the internal structure and composition of two short-period planets situated on opposite sides of the radius valley: HD 15337 b and c. We use new transit photometry and radial velocity data. Methods . We acquired 6 new transit visits with the CHaracterising ExOPlanet Satellite (CHEOPS) and 32 new radial velocity measurements from the High Accuracy Radial Velocity Planet Searcher (HARPS) to improve the accuracy of the mass and radius estimates for both planets. We re-analysed the light curves from TESS sectors 3 and 4 and analysed new data from sector 30, correcting for long-term stellar activity. Subsequently, we performed a joint fit of the TESS and CHEOPS light curves, along with all available RV data from HARPS and the Planet Finder Spectrograph (PFS). Our model fit the planetary signals, stellar activity signal, and instrumental decorrelation model for the CHEOPS data simultaneously. The stellar activity was modelled using a Gaussian-process regression on both the RV and activity indicators. Finally, we employed a Bayesian retrieval code to determine the internal composition and structure of the planets. Results . We derived updated and highly precise parameters for the HD 15337 system. Our improved precision on the planetary parameters makes HD 15337 b one of the most precisely characterised rocky exoplanets, with radius and mass measurements achieving a precision better than 2% and 7%, respectively. We were able to improve the precision of the radius measurement of HD 15337 c to 3%. Our results imply that the composition of HD 15337 b is predominantly rocky, while HD 15337 c exhibits a gas envelope with a mass of at least 0.01 M⊕. Conclusions . Our results lay the groundwork for future studies, which can further unravel the atmospheric evolution of these exoplanets and offer new insights into their composition and formation history as well as the causes behind the radius gap.Peer reviewe
Ejecta masses in Type Ia supernovae : implications for the progenitor and the explosion scenario
Get PDFFunding: This research is supported by NKFIH-OTKA grants K-142534, K-134432, K-138962, FK-134432, and PD134784, NKFIH Élvonal grant KKP-143986, and NKFIH excellence grant TKP2021-NKTA-64 from the National Research, Development and Innovation Office (NKFIH), Hungary. The RC80 and BRC80 telescopes have been supported by the GINOP 2.3.2-15-2016-00033 project from the Government of Hungary, funded by the European Union. J.C.W. and J.V. are supported by NSF grant AST-1813825. Á. S., C.K., and A.B. acknowledge financial support of the KKP137523 “SeismoLab” Élvonal grant of NKFIH, Hungary. B.C. received support from the Lendület Program LP2023-10 of the Hungarian Academy of Sciences. K.V. and L.K. are supported by the Bolyai János Research Scholarship of the Hungarian Academy of Sciences. Financial support from the Austrian– Hungarian Action Foundation grants 112öu1 is also acknowledged. Z.B. is supported by the ÚNKP-22-2 New National Excellence Program of the Ministry for Culture and Innovation from the source of the National Research, Development and Innovation Fund. V.V. is supported by the ÚNKP-22-1 New National Excellence Program of the Ministry for Culture and Innovation from the source of the National Research, Development and Innovation Fund. Z.B., Á.H.-D., N.O.S., and V.V. thank the financial support provided by the undergraduate research assistant program of Konkoly Observatory. L.K. acknowledges the Hungarian National Research, Development and Innovation Office grant OTKA PD-134784. Zs.M.Sz. acknowledges funding from a St Leonards scholarship from the University of St Andrews, and is a member of the International Max Planck Research School (IMPRS) for Astronomy and Astrophysics at the Universities of Bonn and Cologne. K.A.B. is supported by an LSST-DA Catalyst Fellowship; this publication was thus made possible through the support of grant 62192 from the John Templeton Foundation to LSST-DA. A.V.F. is grateful for financial assistance from the Christopher R. Redlich Fund and many other donors. This work makes use of data from the Las Cumbres Observatory global telescope network. The LCO group is supported by NSF grants AST-1911151 and AST-1911225. The HET is a joint project of the University of Texas at Austin, the Pennsylvania State University, Ludwig-Maximilians-Universitat Munchen, and Georg-August-Universitat Gottingen. The HET is named in honor of its principal benefactors, William P. Hobby and Robert E. Eberly. The Low Resolution Spectrograph 2 (LRS2) was developed and funded by the University of Texas at Austin McDonald Observatory and Department of Astronomy, and by Pennsylvania State University. We thank the Leibniz-Institut fur Astrophysik Potsdam (AIP) and the Institut fur Astrophysik Goettingen (IAG) for their contributions to the construction of the integral field units. The authors are grateful to the HET Resident Astronomers and staff members at McDonald Observatory and Las Cumbres Observatory for their excellent work.The progenitor system(s) as well as the explosion mechanism(s) of thermonuclear (Type Ia) supernovae are long-standing issues in astrophysics. Here we present ejecta masses and other physical parameters for 28 recent Type Ia supernovae inferred from multiband photometric and optical spectroscopic data. Our results confirm that the majority of SNe Ia show observable ejecta masses below the Chandrasekhar-limit (having a mean Mej ≈ 1.1 ± 0.3 M⊙), consistent with the predictions of recent sub-MCh explosion models. They are compatible with models assuming either single- or double-degenerate progenitor configurations. We also recover a sub-sample of supernovae within 1.2 M⊙ < Mej < 1.5 M⊙ that are consistent with near-Chandrasekhar explosions. Taking into account the uncertainties of the inferred ejecta masses, about half of our SNe are compatible with both explosion models. We compare our results with those in previous studies, and discuss the caveats and concerns regarding the applied methodology.Peer reviewe
Improving Earth-like planet detection in radial velocity using deep learning
Get PDFFunding: This project has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (grant agreement SCORE No. 851555 and from the Swiss National Science Foundation under the grant SPECTRE (No. 200021_215200). This work has been carried out within the framework of the NCCR PlanetS supported by the Swiss National Science Foundation under grants 51NF40_182901 and 51NF40_205606. FPE would like to acknowledge the Swiss National Science Foundation (SNSF) for supporting research with HARPS-N through the SNSF grants nos. 140649, 152721, 166227, 184618 and 215190. The HARPS-N Instrument Project was partially funded through the Swiss ESA-PRODEX Programme.Context. Many novel methods have been proposed to mitigate stellar activity for exoplanet detection as the presence of stellar activity in radial velocity (RV) measurements is the current major limitation. Unlike traditional methods that model stellar activity in the RV domain, more methods are moving in the direction of disentangling stellar activity at the spectral level. As deep neural networks have already been proven to be one of the most effective tools in data mining, in this work, we explore their potential in the context of Earth-like planet detection in RV measurements. Aims. The goal of this paper is to present a novel convolutional neural network-based algorithm that efficiently models stellar activity signals at the spectral level, enhancing the detection of Earth-like planets. Methods. Based on the idea that the presence of planets can only produce a Doppler shift at the spectral level while the presence of stellar activity can introduce a variation in the profile of spectral lines (asymmetry and depth change), we trained a convolutional neural network to build the correlation between the change in the spectral line profile and the corresponding RV, full width at half maximum (FWHM) and bisector span (BIS) values derived from the classical cross-correlation function. Results. This algorithm has been tested on three intensively observed stars: Alpha Centauri B (HD 128621), Tau ceti (HD 10700), and the Sun. By injecting simulated planetary signals at the spectral level, we demonstrate that our machine learning algorithm can achieve, for HD 128621 and HD 10700, a detection threshold of 0.5 m s−1 in semi-amplitude for planets with periods ranging from 10 to 300 days. This threshold would correspond to the detection of a ~4 M⊕ in the habitable zone of those stars. On the HARPS-N solar dataset, thanks to significantly more data, our algorithm is even more efficient at mitigating stellar activity signals and can reach a threshold of 0.2 m s−1, which would correspond to a 2.2 M⊕ planet on the orbit of the Earth. Conclusions. To the best of our knowledge, it is the first time that such low detection thresholds are reported for the Sun, but also for other stars, and therefore this highlights the efficiency of our convolutional neural network-based algorithm at mitigating stellar activity in RV measurements.Peer reviewe
Relaxed selection in evolution of genes regulating limb development gives clue to variation in forelimb morphology of cetaceans and other mammals
Get PDFFunding: The work by V.T. and P.G. was funded by the National Research Foundation of Ukraine, grant 2020.02/0247 ‘Integration of mammalian organism as a proxy of stability at aquatic and aerial life (as illustrated by skeleton traits)’.Cetaceans have evolved unique limb structures, such as flippers, due to genetic changes during their transition to aquatic life. However, the full understanding of the genetic and evolutionary mechanisms behind these changes is still developing. By examining 25 limb-related protein-coding genes across various mammalian species, we compared genetic changes between aquatic mammals, like whales, and other mammals with unique limb structures such as bats, rodents and elephants. Our findings revealed significant modifications in limb-related genes, including variations in the Hox, GDF5 and Evx genes. Notably, a relaxed selection in several key genes was observed, suggesting a lifting of developmental constraints, which might have facilitated the emergence of morphological innovations in cetacean limb morphology. We also uncovered non-synonymous changes, insertions and deletions in these genes, particularly in the polyalanine tract of HOXD13 , which are distinctive to cetaceans or convergent with other aquatic mammals. These genetic variations correlated with the diverse and specialized limb structures observed in cetaceans, indicating a complex interplay of relaxed selection and specific mutations in mammalian limb evolution.Peer reviewe
The genome sequence of Rhynchonycteris naso, Peters, 1867 (Chiroptera, Emballonuridae, Rhynchonycteris)
Get PDFFunding: SCV was supported by a UKRI Future Leaders Fellowship, (MR/T021985/1), an ERC Consolidator Grant (101001702; BATSPEAK), and a Max Planck Research Group awarded by the Max Planck Society. ECT is a Wellcome collaborator and supported by Irish Research Council Laureate Award IRCLA/2017/58 and Science Foundation Ireland Future Frontiers 19/FFP/6790. MK and MN are supported by the European Research Council (Starting Grant 804352).We present a reference genome assembly from an individual male Rhynchonycteris naso (Chordata; Mammalia; Chiroptera; Emballonuridae). The genome sequence is 2.46 Gb in span. The majority of the assembly is scaffolded into 22 chromosomal pseudomolecules, with the Y sex chromosome assembled.Peer reviewe
Living the experience before you go... but did it meet expectations? The role of virtual reality during hotel bookings
Get PDFVirtual reality (VR) is considered an important technological development to impact the tourism industry. Hotels are constantly attempting to overcome the challenges they face in the presentation of their facilities in the virtual environment. This research has made one of the first attempts to understand VR’s ability to influence tourism consumers’ attitudes and behavioral intentions during the prepurchase phase and postpurchase phase of their purchase journey across three hotel preview styles, namely, (1) VR immersive headsets, (2) 360° VR tour, and (3) a static image website. Through a lab-based experiment with 270-participants, study 1 outlined the positive role of VR on learning about the hotel and visit intentions. Through a questionnaire with 409 actual tourism consumers following a hotel stay, study 2 detailed that VR plays a significant role in managing tourism consumers’ expectations through providing an authentic experience and stimulating the development of detailed mental imagery prior to their visit.Peer reviewe
Training primates to forage in virtual 3D environments
Get PDFFunding: This work was supported by Templeton World Charity Foundation, grant ID: TWCF0314, and European Union's Seventh Framework Program (FP7/2007-2013) / ERC grant agreement no. 609819, SOMICS.Virtual environment software is increasingly being employed as a non-invasive method in primate cognition research. Familiar and novel stimuli can be presented in new ways, opening the door to studying aspects of cognition in captivity which previously may not have been feasible. Despite the increased complexity of visual input compared to more traditional computerised studies, several groups of captive primates have now been trained to navigate virtual three-dimensional environments. Here, we outline a method for training primates to use a computerised virtual foraging task presented on a touchscreen. We document how to tailor this method to groups facing different training challenges. We present data from three groups: touchscreen-experienced chimpanzees (Pan troglodytes), touchscreen-naïve orang-utans (Pongo abelii), and chimpanzees tested in a group setting. Subjects from all groups mastered basic navigation challenges with relative ease (some in as little as 16 days), setting them up for systematic studies of primate cognition within virtual environments. The training method we present is flexible, yet structured, and we encourage other researchers to adapt it to implement virtual environment research with more individuals and across more species.Peer reviewe
Modality, truth and mere picture thinking
Get PDFMany draw the distinction between truth in, and truth at, a possible world. The latter notion purportedly allows for propositions to be true relative to worlds even if they do not exist relative to those same worlds. Despite its wide application, the distinction is controversial. Some think that the notion of truth at a world is unintelligible. Here, I outline and discuss the most influential argument for the unintelligibility of truth at a world, The Picture Thinking Argument. I outline and defend a neglected strategy to respond to this, arguing that if we take seriously the idea that possible worlds represent total ways the world could be, the distinction can be drawn intelligibly.Peer reviewe
(E)-3-Mesityl-1-(2,3,5,6-tetramethylphenyl)prop-2-en-1-one
Get PDFWe report the synthesis and characterisation of the previously unknown (E)-3-Mesityl-1-(2,3,5,6-tetramethylphenyl)prop-2-en-1-one by NMR spectroscopy, IR spectroscopy, melting point, mass spectrometry, and X-ray crystallography.Peer reviewe
The surprising history of abstracts
Get PDFFunding: The research underpinning this essay was funded by the Arts & Humanities Research Council, AH/K001841.Peer reviewe
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