Simultaneous follow-up of planetary transits: revised physical properties for the planetary systems HAT-P-16 and WASP-21

Context. By now more than 300 planets transiting their host star have been found, and much effort is being put into measuring the properties of each system. Light curves of planetary transits often contain deviations from a simple transit shape, and it is generally difficult to differentiate between anomalies of astrophysical nature (e.g. starspots) and correlated noise due to instrumental or atmospheric effects. Our solution is to observe transit events simultaneously with two telescopes located at different observatories. Aims. Using this observational strategy, we look for anomalies in the light curves of two transiting planetary systems and accurately estimate their physical parameters. Methods. We present the first photometric follow-up of the transiting planet HAT-P-16 b, and new photometric observations of WASP-21 b, obtained simultaneously with two medium-class telescopes located in different countries, using the telescope defocussing technique. We modeled these and other published data in order to estimate the physical parameters of the two planetary systems. Results. The simultaneous observations did not highlight particular features in the light curves, which is consistent with the low activity levels of the two stars. For HAT-P-16, we calculated a new ephemeris and found that the planet is 1.3 \sigma colder and smaller (Rb = 1.190 \pm 0.037 RJup) than the initial estimates, suggesting the presence of a massive core. Our physical parameters for this system point towards a younger age than previously thought. The results obtained for WASP-21 reveal lower values for the mass and the density of the planet (by 1.0 \sigma and 1.4 \sigma respectively) with respect to those found in the discovery paper, in agreement with a subsequent study. We found no evidence of any transit timing variations in either system.Comment: 8 pages, 6 figures, accepted for publication in A&

New transit observations for HAT-P-30 b, HAT-P-37 b, TrES-5 b, WASP-28 b, WASP-36 b, and WASP-39 b

We present new transit light curves for planets in six extrasolar planetary systems. They were acquired with 0.4-2.2 m telescopes located in west Asia, Europe, and South America. When combined with literature data, they allowed us to redetermine system parameters in a homogeneous way. Our results for individual systems are in agreement with values reported in previous studies. We refined transit ephemerides and reduced uncertainties of orbital periods by a factor between 2 and 7. No sign of any variations in transit times was detected for the planets studied.Comment: Submitted to Acta Astronomic

Modelling and control of a variable-length flexible beam on inspection ground robot

Stabilising an inverted pendulum on a cart is a well-known control problem. This paper proposes the mechanical and control design for solving the oscillation problem of a variable-length flexible beam mounted on a mobile robot. The system under consideration is the robot PovRob, used at the European Organization for Nuclear Research (CERN) for visual and remote inspection tasks of particle accelerators. The flexible beam mounted on the robot houses cameras and sensors. The innovative aspect of the approach concerns the use of actuated masses mounted at the end of the rod, which induces an impulsive moment due to their inertia and angular acceleration. The modelling of the flexible rod has been suitably simplified in a lumped-parameter system, with dynamic parameters related to the rod’s flexibility. A linearisation of the dynamic model allows a linear-quadratic control to stabilise the system. Experimental results support the identification and the validation of the dynamic model, while simulation results evaluate the performances of the designed control law

Complex AGN feedback in the Teacup galaxy: A powerful ionised galactic outflow, jet-ISM interaction, and evidence for AGN-triggered star formation in a giant bubble

\ua9 2023 The Authors. Context. The z ∼ 0.1 type-2 QSO J1430+1339, known as the Teacup , is a complex galaxy showing a loop of ionised gas ∼10 kpc in diameter, co-spatial radio bubbles, a compact (∼1 kpc) jet, and outflow activity. Its closeness offers the opportunity to study in detail the intricate interplay between the central supermassive black hole (SMBH) and the material in and around the galaxy, both the interstellar medium (ISM) and circumgalactic medium (CGM). Aims. We characterise the spatially resolved properties and effects of the galactic ionised gas outflow and compare them with those of the radio jet and with theoretical predictions to infer its acceleration mechanism. Methods. We used VLT/MUSE optical integral field spectroscopic observations to obtain flux, kinematic, and excitation maps of the extended (up to ∼100 kpc) ionised gas and to characterise the properties of stellar populations. We built radial profiles of the outflow properties as a function of distance from the active nucleus, from kiloparsec up to tens of kiloparsec scales, at ∼1 kpc resolution. Results. We detect a velocity dispersion enhancement (≲300 km s-1) elongated over several kiloparsecs perpendicular to the radio jet, the active galactic nucleus (AGN) ionisation lobes, and the fast outflow, similar to what is found in other galaxies hosting compact, low-power jets, indicating that the jet strongly perturbs the host ISM during its passage. We observe a decreasing trend with distance from the nucleus for the outflow properties (mass outflow rate, kinetic rate, momentum rate). The mass outflow rate drops from around 100 M\ub7 yr-1 in the inner 1-2 kpc to \ue2\uc3 \uc2‰ \ub20.1 M\ub7 yr-1 at 30 kpc. The mass outflow rate of the ionised outflow is significantly higher (∼1-8 times) than the molecular one, in contrast with what is often quoted in AGN. Based on energetic and morphological arguments, the driver of the multi-phase outflow is likely a combination of AGN radiation and the jet, or AGN radiation pressure on dust alone. The outflow mass-loading factor is ∼5-10 and the molecular gas depletion time due to the multi-phase outflow is ≲108 yr, indicating that the outflow can significantly affect the star formation and the gas reservoir in the galaxy. However, the fraction of the ionised outflow that is able to escape the dark matter halo potential is likely negligible. We detect blue-coloured continuum emission co-spatial with the ionised gas loop. Here, stellar populations are younger (≳100-150 Myr) than in the rest of the galaxy (∼0.5-1 Gyr). This constitutes possible evidence for star formation triggered at the edge of the bubble due to the compressing action of the jet and outflow (positive feedback ), as predicted by theory. All in all, the Teacup constitutes a rich system in which AGN feedback from outflows and jets, in both its negative and positive flavours, co-exist

New Transit Observations for HAT-P-30 b, HAT-P-37 b, TrES-5 b, WASP-28 b, WASP-36 b and WASP-39 b

We present new transit light curves for planets in six extrasolar planetary systems. They were acquired with 0.4–2.2 m telescopes located in west Asia, Europe, and South America. When combined with literature data, they allowed us to redetermine system parameters in a homogeneous way. Our results for individual systems are in agreement with values reported in previous studies. We refined transit ephemerides and reduced uncertainties of orbital periods by a factor between 2 and 7. No sign of any variations in transit times was detected for the planets studied.Fil: Maciejewski, G.. Nicolaus Copernicus University; PoloniaFil: Dimitrov, D.. Bulgarian Academy Of Sciences; BulgariaFil: Mancini, L.. Max Planck Institute for Astronomy; Alemania. Osservatorio Astrofisico Di Torino; Italia. Istituto Nazionale di Astrofisica; ItaliaFil: Southworth, J.. Keele University; Reino UnidoFil: Ciceri, S.. Max Planck Institute For Astronomy; AlemaniaFil: D'Ago, G.. Istituto Internazionale per gli Alti Studi ; ItaliaFil: Bruni, I.. Osservatorio Astrofisico di Bologna; Italia. Istituto Nazionale di Astrofisica; ItaliaFil: Raetz, St.. Universitat Erlangen-nurmberg. Astronomisches Institut-dr. Karl Remeis-sternwarte & Ecap; Alemania. European Space Agency; Países BajosFil: Nowak, G.. Instituto de Astrofísica de Canarias; España. Nicolaus Copernicus University; Polonia. Universidad de La Laguna; EspañaFil: Ohlert, J.. University of Applied Sciences; Alemania. Michael Adrian Observatorium; AlemaniaFil: Puchalski, D.. Nicolaus Copernicus University; PoloniaFil: Saral, G.. Istanbul University; Turquía. University Of Geneva (ug);Fil: Derman, E.. Ankara University; TurquíaFil: Petrucci, Romina Paola. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Astronomía Teórica y Experimental. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba. Instituto de Astronomía Teórica y Experimental; ArgentinaFil: Jofré, E.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Astronomía Teórica y Experimental. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba. Instituto de Astronomía Teórica y Experimental; ArgentinaFil: Seeliger, M.. Universitat Erlangen-nurmberg. Astronomisches Institut-dr. Karl Remeis-sternwarte & Ecap; AlemaniaFil: Henning, T.. Max Planck Institute for Astronomy; Alemani

Complex AGN feedback in the Teacup galaxy. A powerful ionised galactic outflow, jet-ISM interaction, and evidence for AGN-triggered star formation in a giant bubble

The $z$~0.1 type-2 QSO J1430+1339 (the 'Teacup') is a complex galaxy showing a loop of ionised gas ~10 kpc in diameter, co-spatial radio bubbles, a compact (~1 kpc) jet, and outflow activity. We used VLT/MUSE optical integral field spectroscopic observations to characterise the properties and effects of the galactic ionised outflow from kpc up to tens of kpc scales and compare them with those of the radio jet. We detect a velocity dispersion enhancement (>300 km/s) elongated over several kpc perpendicular to the radio jet, the AGN ionisation lobes, and the fast outflow, similar to what is found in other galaxies hosting compact, low-power jets, indicating that the jet strongly perturbs the host ISM. The mass outflow rate decreases with distance from the nucleus, from around 100 $M_\odot$/yr in the inner 1-2 kpc to <0.1 $M_\odot$/yr at 30 kpc. The ionised mass outflow rate is ~1-8 times higher than the molecular one, in contrast with what is often quoted in AGN. The driver of the multi-phase outflow is likely a combination of AGN radiation and the jet. The outflow mass-loading factor (~5-10) and the molecular gas depletion time (<10$^8$ yr) indicate that the outflow can significantly affect the star formation and the gas reservoir in the galaxy. However, the fraction of the ionised outflow that is able to escape the dark matter halo potential is likely negligible. We detect blue-coloured continuum emission co-spatial with the ionised gas loop. Here, stellar populations are younger (<100-150 Myr) than in the rest of the galaxy (~0.5-1 Gyr). This constitutes possible evidence for star formation triggered at the edge of the bubble due to the compressing action of the jet and outflow ('positive feedback'), as predicted by theory. All in all, the Teacup constitutes a rich system in which AGN feedback from outflows and jets, in both its negative and positive flavours, co-exist.Comment: 26 pages, 16 figures; Astronomy & Astrophysics, in pres

Building the Largest Spectroscopic Sample of Ultracompact Massive Galaxies with the Kilo Degree Survey

Ultracompact massive galaxies (ucmgs), i.e., galaxies with stellar masses M∗ > 8× 10-10 M⊙ and effective radii R e< 1.5 kpc, are very rare systems, in particular at low and intermediate redshifts. Their origin as well as their number density across cosmic time are still under scrutiny, especially because of the paucity of spectroscopically confirmed samples. We have started a systematic census of ucmg candidates within the ESO Kilo Degree Survey, together with a large spectroscopic follow-up campaign to build the largest possible sample of confirmed ucmgs. This is the third paper of the series and the second based on the spectroscopic follow-up program. Here, we present photometrical and structural parameters of 33 new candidates at redshifts 0.15≲ z≲ 0.5 and confirm 19 of them as ucmgs, based on their nominal spectroscopically inferred M and R e. This corresponds to a success rate of ∼ 58%, nicely consistent with our previous findings. The addition of these 19 newly confirmed objects allows us to fully assess the systematics on the system selection-and to finally reduce the number density uncertainties. Moreover, putting together the results from our current and past observational campaigns and some literature data, we build the largest sample of ucmgs ever collected, comprising 92 spectroscopically confirmed objects at 0.1≲ z≲ 0.5. This number raises to 116, allowing for a 3σ tolerance on the M∗ and Re thresholds for the ucmg definition. For all these galaxies, we have estimated the velocity dispersion values at the effective radii, which have been used to derive a preliminary mass-velocity dispersion correlation

INSPIRE: INvestigating stellar population in RElics: II. First data release (DR1)

[Context] The INvestigating Stellar Population In RElics (INSPIRE) is an ongoing project targeting 52 ultra-compact massive galaxies at 0.1 2) through a short and intense star formation burst, and then have evolved passively and undisturbed until the present day. Relics provide a unique opportunity to study the mechanisms of star formation at high-z. [Aims] INSPIRE is designed to spectroscopically confirm and fully characterise a large sample of relics, computing their number density in the redshift window 0.1 < z < 0.5 for the first time, thus providing a benchmark for cosmological galaxy formation simulations. In this paper, we present the INSPIRE Data Release (DR1), comprising 19 systems with observations completed in 2020. [Methods] We use the methods already presented in the INSPIRE Pilot, but revisiting the 1D spectral extraction. For the 19 systems studied here, we obtain an estimate of the stellar velocity dispersion, fitting the two XSH arms (UVB and VIS) separately at their original spectral resolution to two spectra extracted in different ways. We estimate [Mg/Fe] abundances via line-index strength and mass-weighted integrated stellar ages and metallicities with full spectral fitting on the combined (UVB+VIS) spectrum. [Results] For each system, different estimates of the velocity dispersion always agree within the errors. Spectroscopic ages are very old for 13/19 galaxies, in agreement with the photometric ones, and metallicities are almost always (18/19) super-solar, confirming the mass-metallicity relation. The [Mg/Fe] ratio is also larger than solar for the great majority of the galaxies, as expected. We find that ten objects formed more than 75% of their stellar mass (M∗) within 3 Gyr from the big bang and classify them as relics. Among these, we identify four galaxies that had already fully assembled their M∗ by that time and are therefore 'extreme relics' of the ancient Universe. Interestingly, relics, overall, have a larger [Mg/Fe] and a more metal-rich stellar population. They also have larger integrated velocity dispersion values compared to non-relics (both ultra-compact and normal-size) of similar stellar mass. [Conclusions ]The INSPIRE DR1 catalogue of ten known relics is the largest publicly available collection, augmenting the total number of confirmed relics by a factor of 3.3, and also enlarging the redshift window. The resulting lower limit for the number density of relics at 0.17 < z < 0.39 is ρ ∼ 9.1 × 10-8 Mpc-3.CS is supported by an ‘Hintze Fellow’ at the Oxford Centre for Astrophysical Surveys, which is funded through generous support from the Hintze Family Charitable Foundation. CS, CT, FLB, AG, and SZ acknowledge funding from the INAF PRIN-INAF 2020 program 1.05.01.85.11. AFM has received financial support through the Postdoctoral Junior Leader Fellowship Programme from ‘La Caixa’ Banking Foundation (LCF/BQ/LI18/11630007). GD acknowledges support from CONICYT project Basal AFB-170002. DS is a member of the International Max Planck Research School (IMPRS) for Astronomy and Astrophysics at the Universities of Bonn and Cologne

INSPIRE: INvestigating Stellar Population in RElics: I. Survey presentation and pilot study

[Context] Massive elliptical galaxies are thought to form through a two-phase process. At early times (z > 2), an intense and fast starburst forms blue and disk-dominated galaxies. After quenching, the remaining structures become red, compact, and massive (i.e. red nuggets). Then, a time-extended second phase, which is dominated by mergers, causes structural evolution and size growth. Given the stochastic nature of mergers, a small fraction of red nuggets survive, without any interaction, massive and compact until today: these are relic galaxies. Since this fraction depends on the processes dominating the size growth, counting relics at low-z is a valuable way of disentangling between different galaxy evolution models. [Aims] In this paper, we introduce the INvestigating Stellar Population In RElics (INSPIRE) Project, which aims to spectroscopically confirm and fully characterise a large number of relics at 0:1z0:5. We focus here on the first results based on a pilot study targeting three systems, representative of the whole sample. [Methods] For these three candidates, we extracted 1D optical spectra over an aperture of r = 0:4000, which comprises 30% of the galaxies’ light, and we obtained the line-of-sight integrated stellar velocity and velocity dispersion. We also inferred the stellar [/Fe] abundance from line-index measurements and mass-weighted age and metallicity from full-spectral fitting with single stellar population models. [Results] Two galaxies have large integrated stellar velocity dispersion values (250 km s), confirming their massive nature. They are populated by stars with super-solar metallicity and [/Fe]. Both objects have formed 80% of their stellar mass within a short (0:5:0 Gyr) initial star formation episode occurred only 1 Gyr after the Big Bang. The third galaxy has a more extendedstar formation history and a lower velocity dispersion. Thus we confirm two out of three candidates as relics. [Conclusions] This paper is the first step towards assembling the final INSPIRE catalogue that will set stringent lower limits on the number density of relics at z0:5, thus constituting a benchmark for cosmological simulations, and their predictions on number densities, sizes, masses, and dynamical characteristics of these objects.CS is supported by a Hintze Fellowship at the Oxford Centre for Astrophysical Surveys, which is funded through generous support from the Hintze Family Charitable Foundation. C.S. is also very grateful to Ortwin Gerhard and his ?Dynamics Group? at the Max-Planck-Institut f?r Extraterrestrische Physik (MPE, Garching by Munich) for interesting and constructive discussions. C.T., A.G., L.H. and S.Z. acknowledge funding from the INAF PRIN-SKA 2017 programme 1.05.01.88.04. G.D. acknowledges support from CONICYT project Basal AFB-170002. AFM has received financial support through the Postdoctoral Junior Leader Fellowship Programme from La Caixa Banking Foundation (LCF/BQ/LI18/11630007). N.R.N. acknowledges financial support from the One hundred top talent programme of Sun Yat-sen University, Grant N. 71000-18841229. D.S. is a member of the International Max Planck Research School (IMPRS) for Astronomy and Astrophysics at the Universities of Bonn and Cologne

INSPIRE: INvestigating Stellar Population In RElics -- I. Survey presentation and pilot program

Massive ETGs are thought to form through a two-phase process. At early times, an intense and fast starburst forms blue and disk-dominated galaxies. After quenching, the remaining structures become red, compact and massive, i.e., 'red nuggets'. Then, a time-extended second phase which is dominated by mergers, causes structural evolution and size growth. Given the stochastic nature of mergers, a small fraction of red nuggets survives, without any interaction, massive and compact until today: relic galaxies. Since this fraction depends on the processes dominating the size growth, counting relics at low-z is a valuable way to disentangle between different galaxy evolution models. In this paper, we introduce the INvestigating Stellar Population In RElics (INSPIRE) Project, that aims at spectroscopically confirming and fully characterizing a large number of relics at 0.1<z<0.5. We focus here on the first results based on a pilot program targeting three systems, representative of the whole sample. For these, we extract 1D optical spectra over an aperture comprising ~30 % of the galaxies light, and obtain line-of-sight integrated stellar velocity and velocity dispersion. We also infer the stellar [$\alpha$/Fe] abundance from line-index measurements and mass-weighted age and metallicity from full-spectral fitting with single stellar population models. Two galaxies have large integrated stellar velocity dispersion values, confirming their massive nature. They are populated by stars with super-solar metallicity and [$\alpha$/Fe]. Both objects have formed >80 % of their stellar mass within a short (0.5 - 1.0 Gyrs) initial star formation episode occurred only ~1 Gyr after the Big Bang. The third galaxy has a more extended star formation history and a lower velocity dispersion. Thus we confirm two out of three candidates as relics.Comment: 19 pages, 14 figures, accepted for publication in A&