Astronomy & Astrophysics最新文献

{"title":"Discovery of HCCCH_2CCH in TMC-1 with the QUIJOTE line survey","authors":"R. Fuentetaja, M. Ag'undez, C. Cabezas, B. Tercero, N. Marcelino, J. R. Pardo, P. D. Vicente, J. Cernicharo","doi":"10.1051/0004-6361/202348777","DOIUrl":"https://doi.org/10.1051/0004-6361/202348777","url":null,"abstract":"We present the first detection in space of 1,4-pentadiyne. It has\u0000been found towards TMC-1 with the QUIJOTE line survey in the 31-50 GHz range. \u0000We observed a total of 17 transitions with $J$ = 2 up to 13 and $K_a$ = \u00000,1 and 2. The observed transitions allowed us to derive a rotational temperature \u0000of 9.5 pm 0.5 K and a column density of (5.0 pm 0.5)times 1012 cm$^ $. \u0000This molecule was the last non-cyclic isomer of the C$_5$H$_4$ family that could be detected via radio astronomy. A computational chemistry study was performed to determine the energies of the five most stable isomers. The isomer ($c$-C$_3$H$_3$CCH) has a considerably higher energy than the \u0000others, and it has not yet been detected.\u0000To better understand the chemical reactions involving these species, \u0000we compared the ethynyl and cyano derivatives. The observed \u0000abundances of these species are in good agreement with the branching ratios of \u0000the formation reactions studied with our chemical model of TMC-1.","PeriodicalId":505693,"journal":{"name":"Astronomy & Astrophysics","volume":"31 7","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141663803","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A new census of dust and polycyclic aromatic hydrocarbons at z=0.7-2 with JWST MIRI","authors":"I. Shivaei, S. Alberts, M. Florian, G. Rieke, S. Wuyts, Sarah Bodansky, J. Andrew Bunker, J. Alex Cameron, M. Curti, F. d’Eugenio, U. Dudzevičiūtė, Zhiyuan Ji, D. Benjamin Johnson, I. Kramarenko, J. Lyu, J. Matthee, Jane Morrison, R. Naidu, G. Pablo P'erez-Gonz'alez, Naveen A. Reddy, B. Robertson, Yang Sun, S. Tacchella, K. Whitaker, C. Christina Williams, N.A. Christopher Willmer, J. Witstok, M. Xiao, Yongda Zhu","doi":"10.1051/0004-6361/202449579","DOIUrl":"https://doi.org/10.1051/0004-6361/202449579","url":null,"abstract":"This paper utilises the James Webb Space Telescope (JWST) Mid-Infrared Instrument (MIRI) to extend the observational studies of dust and polycyclic aromatic hydrocarbon (PAH) emission to a new mass and star formation rate (SFR) parameter space beyond our local Universe. The combination of fully sampled spectral energy distributions (SEDs) with multiple mid-infrared (mid-IR) bands and the unprecedented sensitivity of MIRI allows us to investigate dust obscuration and PAH behaviour from $z=0.7$ up to $z=2$ in typical main-sequence galaxies. Our focus is on constraining the evolution of PAH strength and the dust-obscured luminosity fraction before and during cosmic noon, the epoch of peak star formation activity in the Universe. um um um um imaging data, enhancing our understanding of the physical characteristics of dust within these galaxies. We find a strong correlation between the fraction of dust in PAHs (PAH fraction qpah ) with stellar mass. Moreover the sub-sample with robust qpah measurements ($N=216$) shows a similar behaviour between qpah and gas-phase metallicity to that at $z suggesting a universal relation: qpah is constant ($ 3.4$) above a metallicity of $Z odot $ and decreases to $<1$ at metallicities $ odot $. This indicates that metallicity is a good indicator of the interstellar medium properties that affect the balance between the formation and destruction of PAHs. The lack of a redshift evolution from $z 0-2$ also implies that above $Z odot $ the PAH emission effectively traces obscured luminosity and the previous locally calibrated PAH-SFR calibrations remain applicable in this metallicity regime.\u0000 We observe a strong correlation between the obscured UV luminosity fraction (ratio of obscured to total luminosity) and stellar mass. Above the stellar mass of $M_*>5 Msun on average, more than half of the emitted luminosity is obscured, while there exists a non-negligible population of lower-mass galaxies with $>50$ obscured fractions. At a fixed mass, the obscured fraction correlates with SFR surface density. This is a result of higher dust covering fractions in galaxies with more compact star-forming regions. Similarly, galaxies with high IRX (IR to UV luminosity) at a given mass or UV continuum slope (beta ) tend to have higher Ssfr and shallower attenuation curves, owing to their higher effective dust optical depths and more compact star-forming regions.","PeriodicalId":505693,"journal":{"name":"Astronomy &amp; Astrophysics","volume":"34 8","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141663715","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The impact of improved estimates of radio star astrometric models on the alignment of the Gaia bright reference frame to ICRF3","authors":"S. Lunz, James M. Anderson, Ming H. Xu, R. Heinkelmann, O. Titov, Jean-Francois Lestrade, Megan C. Johnson, Fengchun Shu, Wen Chen, Alexey Melnikov, Andrei Mikhailov, Jamie McCallum, Yulia Lopez, Pablo de Vicente Abad, Harald Schuh","doi":"10.1051/0004-6361/202142081","DOIUrl":"https://doi.org/10.1051/0004-6361/202142081","url":null,"abstract":"We investigated the residual orientation offset and spin between the bright ($G 13$,mag) frame of the $Gaia$ Early Data Release 3 ($Gaia$ EDR3) and the third realization of the International Celestial Reference Frame (ICRF3). For this purpose, six rotation parameters (orientation offset and its time derivative, the spin), as well as corrections to the $Gaia$ astrometric model for each star involved, are fitted to the differences in the astrometric models derived from very long baseline interferometry (VLBI) and $Gaia$. This study aims to find reliable estimates for the rotation parameters between the two frames. We reprocessed our previous analyses while taking into account the effect of Galactocentric acceleration on the VLBI observations. Furthermore, we replaced VLBI data for 12 stars by improved estimates of models of stellar motion from combining historical data with the new positions, rather than including the new observations directly as single-epoch positions in the analysis of the rotation parameters. Additionally, we replaced the model positions by positions obtained without correcting the calibrator data for source structure whenever possible to better reference the star position to ICRF3. In the same fashion, the VLBI proper motion and parallax were included for two of the stars for the first time, and data for five new stars were added. The iterative solutions for the spin parameters show less scatter in the $X$ component when the new models of stellar motion from VLBI are applied. The mean formal errors of the spin parameters decrease by about percent whereas those of the orientation offsets increase by about percent . Small additional improvements in the mean formal error were achieved by including new VLBI data and by excluding stars that produce offsets in the iterative rotation parameter estimates from the beginning. \u0000 The orientation offset $ epsilon_Z(T) $ and the spin $ omega_Z $ of the final baseline solution of this work were found to be \u0000 (+0.322, +0.228, +0.163)pm (0.203, 0.251, 0.155) mas and (+0.034, +0.072 )pm (0.023, 0.025, 0.023) year . \u0000 As a consequence, no significant orientation offset of $Gaia$ EDR3 toward ICRF3 is detected; however, the spin $ is statistically significant at the 3sigma level. The rotation parameters between the $Gaia$ and VLBI frames in the $Y$ direction remain the least well determined in terms of formal errors. The impact of Galactocentric acceleration on the rotation parameter analysis was found to be negligible with the currently available VLBI data. As a result, it was found that the uncorrected bright $Gaia$ frame exhibits a closer alignment with ICRF3 compared to the corrected frame.","PeriodicalId":505693,"journal":{"name":"Astronomy &amp; Astrophysics","volume":" 32","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141670439","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Revealing the inner workings of the lensed quasar SDSS J1339+1310 : Insights from microlensing analysis","authors":"C. Fian, J. A. Munoz, J. Jim'enez-Vicente, E. Mediavilla, D. Chelouche, S. Kaspi, R. For'es-Toribio","doi":"10.1051/0004-6361/202450151","DOIUrl":"https://doi.org/10.1051/0004-6361/202450151","url":null,"abstract":"We aim to unveil the structure of the continuum and broad-emission line (BEL) emitting regions in the gravitationally lensed quasar SDSS J1339+1310 by examining the distinct signatures of microlensing present in this system. Our study involves a comprehensive analysis of ten years (2009--2019) of photometric monitoring data and seven spectroscopic observations acquired between 2007 and 2017. This work focuses on the pronounced deformations in the BEL profiles between images A and B, alongside the chromatic changes in their adjacent continua and the striking microlensing variability observed in the $r$-band light curves. We employed a statistical model to quantify the distribution and impact of microlensing magnifications and utilized a Bayesian approach to estimate the dimensions of various emission regions within the quasar. To establish a baseline relatively free of microlensing effects, we used the cores of the emission lines as a reference. The analysis of the $r$-band light curves reveals substantial microlensing variability in the rest-frame UV continuum, suggesting that image B is amplified relative to image A by a factor of up to six. This finding is corroborated by pronounced microlensing-induced distortions in all studied BEL profiles (Lyalpha , Si IV, C IV, C III","PeriodicalId":505693,"journal":{"name":"Astronomy &amp; Astrophysics","volume":" 21","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141668327","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Extragalactic globular cluster near-infrared spectroscopy. I. Integrated near-infrared spectra of Centaurus A/NGC 5128","authors":"L. Dahmer-Hahn, A. Chies-Santos, E. Eftekhari, E. Zanatta, R. Riffel, A. Vazdekis, A. Villaume, M. Beasley, A.E. Lassen","doi":"10.1051/0004-6361/202449570","DOIUrl":"https://doi.org/10.1051/0004-6361/202449570","url":null,"abstract":"One way to constrain the evolutionary histories of galaxies is to analyse their stellar populations. In the local Universe, our understanding of the stellar population properties of galaxies has traditionally relied on the study of optical absorption and emission-line features. In order to overcome limitations intrinsic to this wavelength range, such as the age-metallicity degeneracy and the high sensitivity to dust reddening, we must use wavelength ranges beyond the optical. The near-infrared (NIR) offers a possibility to extract information on spectral signatures that are not as obvious in traditional optical bands. Moreover, with the current and forthcoming generation of instrumentation focusing on the NIR, it is mandatory to explore possibilities within this wavelength range for nearby-Universe galaxies. However, although the NIR shows great potential, we are only beginning to understand it. Widely used techniques such as a full spectral fitting and line strength indices need to be tested on systems that are as close to simple stellar populations as possible, and the result from the techniques need to be compared to the yields from a traditional optical analysis. We present a NIR spectral survey of extragalactic globular clusters (GCs). The set was composed of 21 GCs from the Centaurus,A galaxy that were obtained with SOAR/TripleSpec4, which covered the sim 1.0-2.4,mu m range with a spectral resolution ($ R= lambda lambda $) of 3500. These spectra cover Hbeta equivalent widths between 0.98 A and 4.32 A and MgFe ' between 0.24 A and 3.76 A This set was ideal for performing absorption band measurements and a full spectral fitting, and it can be used for kinematic studies and age and abundance measurements. With this library, we expect to be able to probe the capabilities of NIR models, as well as to further improve stellar population estimates for the GCs around the Centaurus A galaxy.","PeriodicalId":505693,"journal":{"name":"Astronomy &amp; Astrophysics","volume":"123 32","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141667578","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Asteroid follow-up and precovery problem: Partial banana mapping solution","authors":"D.E. Vavilov, D. Hestroffer","doi":"10.1051/0004-6361/202449830","DOIUrl":"https://doi.org/10.1051/0004-6361/202449830","url":null,"abstract":"Precovery of asteroids, that is, finding older observations of already discovered asteroids, allows us to refine our knowledge of their orbits, glean information about close encounters and the probability of\u0000collisions with Earth, and to determine some dynamical and physical properties, such as the Yarkovsky acceleration. Existing approaches generally look for an observation next to the predicted position from the nominal orbit, and often do not take into account the whole uncertainty distribution of coordinates We aim to develop a computationally fast technique for predicting the possible spherical coordinates of near-Earth asteroids in order to find observations in existing catalogs or archived observations (plates, CCDs, etc.). We modified the partial banana mapping method, and used it to estimate impact probabilities of asteroids with the Earth. For a near-Earth asteroid, a Gaussian law for the equinoctial orbital elements well approximates the uncertainty region of the object at the epoch of the observation. We sample virtual asteroids on the main line of the curved uncertainty region at the epoch of observation project all of them with their small uncertainty vicinity onto the celestial sphere, and evaluate the brightness of the asteroids. We also estimate the probability of finding the asteroids on the image, and the length of the uncertainty region (which shows the quality of the orbit) in order to establish a priority list among the images. The higher the probability and the poorer the quality of the orbit, the more interesting it is to find the object for further improvement of its orbit and to refined its impact probability computation. We demonstrate the applicability of the developed method. We tested it on the case of precovery observations of asteroid (506074) Svarog (provisional designation 2015 UM$_ $) as if it had recently been discovered, meaning the orbit is obtained with only 3 months of observations. In this case, we estimated a probability of precovery of about 10, predicted the possible positions, and actually found the object close to the constructed uncertainty region. The nominal position is outside of the image's field of view, meaning that conventional methods would fail . The uncertainty region is curved and asymmetric, which shows that using only the covariance matrix of celestial coordinates for the nominal orbit would poorly approximate the actual uncertainty region in the place of the sky, preventing the asteroid from being found. The developed method selects interesting images and guides us in our search for asteroids on them, even if the position predicted for the nominal orbit is out of the image window.","PeriodicalId":505693,"journal":{"name":"Astronomy &amp; Astrophysics","volume":" 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141671399","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spectral properties of bright deposits in permanently shadowed craters on Ceres","authors":"Stefan Schröder, Norbert Schörghofer, Erwan Mazarico, U. Carsenty","doi":"10.1051/0004-6361/202450247","DOIUrl":"https://doi.org/10.1051/0004-6361/202450247","url":null,"abstract":"Bright deposits in permanently shadowed craters on Ceres are thought to harbor water ice. However, the evidence for water ice presented thus far is indirect. We aim to directly detect the spectral characteristics of water ice in bright deposits present in permanently shadowed regions (PSRs) in polar craters on Ceres. We analyzed narrowband images of four of the largest shadowed bright deposits acquired by the Dawn Framing Camera to reconstruct their reflectance spectra, carefully considering issues such as in-field stray light correction and image compression artifacts. The sunlit portion of a polar deposit known to harbor water ice has a negative (blue) spectral slope of $-58 12$ $ relative to the background in the visible wavelength range. We find that the PSR bright deposits have similarly blue spectral slopes, consistent with a water ice composition. Based on the brightness and spectral properties, we argue that the ice is likely present as particles of high purity. Other components such as phyllosilicates may be mixed in with the ice. Salts are an unlikely brightening agent given their association with cryovolcanic processes, of which we find no trace. Our spectral analysis strengthens the case for the presence of water ice in permanently shadowed craters on Ceres.","PeriodicalId":505693,"journal":{"name":"Astronomy &amp; Astrophysics","volume":" 29","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141673283","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"First detection of the J−1 → (J− 1)0 − E methanol maser transitions at J = 7 and 10","authors":"P. Humire, G. Ortiz-Léon, A. Hernández-Gómez, Wenjin Yang, Christian Henkel, Sergio Martín","doi":"10.1051/0004-6361/202451008","DOIUrl":"https://doi.org/10.1051/0004-6361/202451008","url":null,"abstract":"Class,I methanol masers provide sensitive information about the shocked environment around star-forming regions. Among the brightest Class I methanol masers, we have those in the -E$ line series, currently reported for the $J=4-9$ transitions, with the only exception being the $J=7$ one at 181.295 GHz, and never expanded to higher $J$ transitions. We aim to search for population inversion in the $7_ -E$ and $10_ -E$ methanol transition lines at 181.295 and 326.961,GHz, respectively, and also extend the number of known low-mass star-forming sources harboring Class,I methanol masers. We employed the \u0000 \u0000 Atacama Pathfinder Experiment (APEX) 12,m telescope to survey low-mass Galactic sources, focusing on methanol emission lines. We built rotation diagrams for all sources with detected $J=7$ methanol line transitions, while employing radiative transfer modeling (both in and out of local thermodynamic equilibrium) to characterize methanol excitation conditions in detail for one specific source with detected masers. We detected the $7_ -E$ and $10_ -E$ methanol transitions in 6 out of 19 sources. Among them, we firmly determined the $10_ -E$ maser nature in CARMA,7, L1641N, NGC,2024, and Serpens FIRS, and we show evidence for the presence of inverted population emission in the -E$ line toward CARMA,7 and L1641N. This represents the first report of methanol maser emission in these particular transitions. Our study supports previous works indicating that conditions for Class,I methanol maser emission are satisfied in low-mass star-forming regions and expands the range of detectable frequencies toward higher values.","PeriodicalId":505693,"journal":{"name":"Astronomy &amp; Astrophysics","volume":" 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141673677","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Galaxy populations and redshift dependence of the correlation between infrared and radio luminosity","authors":"G. De Zotti, M. Bonato, M. Giulietti, M. Massardi, M. Negrello, H. Algera, J. Delhaize","doi":"10.1051/0004-6361/202449313","DOIUrl":"https://doi.org/10.1051/0004-6361/202449313","url":null,"abstract":"We argue that the difference in infrared-to-radio luminosity ratio between local and high-redshift star-forming galaxies reflects the alternative physical conditions ---including magnetic field configurations--- of the dominant population of star-forming galaxies in different redshift ranges. We define three galactic types, based on our reference model, with reference to ages of stellar populations. ``Normal'' late-type galaxies dominate the star formation in the nearby Universe; ``starburst'' galaxies take over at higher redshifts, up to $z 1.5$; while ``protospheroidal'' galaxies dominate at high redshift. A reanalysis of data from the COSMOS field combined with literature results shows that, for each population, the data are consistent with an almost redshift-independent mean value of the parameter IR $, which quantifies the infrared--radio correlation. However, we find a hint of an upturn of the mean $q_ IR $ at $z 3.5$ consistent with the predicted dimming of synchrotron emission due to cooling of relativistic electrons by inverse Compton scattering off the cosmic microwave background. The typical stellar masses increase from normal, to starburst, and to protospheroidal galaxies, accounting for the reported dependence of the mean IR $ on stellar mass. Higher values of $q_ IR $ found for high-$z$ strongly lensed dusty galaxies selected at $500 might be explained by differential magnification.","PeriodicalId":505693,"journal":{"name":"Astronomy &amp; Astrophysics","volume":" 47","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141675574","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Photo-dynamical characterisation of the TOI-178 resonant chain. Exploring the robustness of transit-timing variations and radial velocity mass characterisations","authors":"A. Leleu, J. Delisle, L. Delrez, E. M. Bryant, A. Brandeker, H. Osborn, N. Hara, T. G. Wilson, N. Billot, M. Lendl, D. Ehrenreich, H. Chakraborty, M. Günther, M. Hooton, Y. Alibert, R. Alonso, D. R. Alves, D. Anderson, I. Apergis, D. Armstrong, T. Bárczy, D. Barrado Navascues, S. Barros, M. Battley, Wolfgang Baumjohann, D. Bayliss, T. Beck, W. Benz, L. Borsato, C. Broeg, M. Burleigh, S. Casewell, A. Collier Cameron, A. Correia, S. Csizmadia, P. E. Cubillos, M. B. Davies, M. Deleuil, A. Deline, O. Demangeon, B. Demory, A. Derekas, B. Edwards, A. Erikson, A. Fortier, L. Fossati, M. Fridlund, D. Gandolfi, K. Gazeas, E. Gillen, M. Gillon, M. R. Goad, M. Güdel, F. Hawthorn, A. Heitzmann, C. Helling, K. Isaak, J. S. Jenkins, J. Jenkins, A. Kendall, L. Kiss, J. Korth, K. Lam, J. Laskar, D. Latham, A. Lecavelier des Etangs, D. Magrin, P. Maxted, J. McCormac, C. Mordasini, M. Moyano, V. Nascimbeni, G. Olofsson, A. Osborn, R. Ottensamer, I. Pagano, E. Pallé, G. Peter, G. Piotto, D. Pollacco, D. Queloz, R. Ragazzoni","doi":"10.1051/0004-6361/202450212","DOIUrl":"https://doi.org/10.1051/0004-6361/202450212","url":null,"abstract":"The TOI-178 system consists of a nearby, late-K-dwarf with six transiting planets in the super-Earth to mini-Neptune regime, with radii ranging from sim 1.1 to 2.9 $R_ oplus $ and orbital periods between 1.9 and 20.7 days. All the planets, but the innermost one, form a chain of Laplace resonances. \u0000 \u0000 The fine-tuning and fragility of such orbital configurations ensure that no significant scattering or collision event has taken place since the formation and migration of the planets in the protoplanetary disc, thereby providing important anchors for planet formation models. We aim to improve the characterisation of the architecture of this key system and, in particular, the masses and radii of its planets. In addition, since this system is one of the few resonant chains that can be characterised by both photometry and radial velocities, we propose to use it as a test bench for the robustness of the planetary mass determination with each technique. We performed a global analysis of all the available photometry from CHEOPS, TESS and NGTS, and radial velocity from ESPRESSO, using a photo-dynamical modelling of the light curve. We also tried different sets of priors on the masses and eccentricity, as well as different stellar activity models, to study their effects on the masses estimated by transit-timing variations (TTVs) and radial velocities (RVs). We demonstrate how stellar activity prevents a robust mass estimation for the three outer planets using radial velocity data alone. \u0000 We also show that our joint photo-dynamical and radial velocity analysis has resulted in a robust mass determination for planets $c$ to $g$, with precision of $ 12$ for the mass of planet $c$, and better than $10$ for planets $d$ to $g$. The new precisions on the radii range from $2$ to $3$. The understanding of this synergy between photometric and radial velocity measurements will be valuable for the PLATO mission. We also show that TOI-178 is indeed currently locked in the resonant configuration, librating around an equilibrium of the chain.","PeriodicalId":505693,"journal":{"name":"Astronomy &amp; Astrophysics","volume":" 13","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141673436","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}