Abstracts of Large Programmes and Public Spectroscopic Surveys scheduled in Period 106


This list of OPC approved Large Programmes (LPs) is updated every observing period.



Giant planets are thought to form via core-accretion, whereby rocky/icy cores form early on in the protoplanetary disk, and then at a critical point attract gas from the disk to build up an atmosphere. The precise composition of the core, particularly the ice-mass fraction, tells us about the formation process and where in the protoplanetary disk the planet formed. In most cases the gaseous envelope hides this core, meaning we cannot determine its composition. However in situations where the planet is exposed to intense radiation, that gaseous envelope is lost, providing us with a unique opportunity to study the exposed core. We target cores by observing planets subject to gas evaporation, with orbital period $<5$d and radius between 1.8 and 4 $R_\oplus$. With this large program proposal, we want to measure the masses of up to 30 new planetary cores across the parameter space, studying the core composition, formation process and mass distribution statistically for the first time. This will in turn allow us to determine where in the disk these cores formed, and thus give us insight into where planet formation occurs and how far these planets migrated since their initial formation. We will source our targets initially from \textit{K2} planet discoveries, updating to include bright \textit{TESS} candidates from mid-P102 onwards. Our science goals can be met independently of \textit{TESS}, allowing the characterisation of 12 new cores using \textit{K2} targets alone.




We propose to exploit ALMA continuum surveys of submillimetre sources in the UKIDSS/UDS, COSMOS and GOODS-S/ECDFS fields, which provide precise identifications and multiwavelength properties for $\sim$\,1,100 submillimetre galaxies (SMGs). SMGs represent a population of massive, strongly star-forming galaxies at $z\sim$\,1--4, which have been empirically claimed to have many of the properties expected for the progenitors of local spheroidal galaxies. To test this claim quantitatively and so determine their role in the formation of today's massive galaxies, we propose to target 545 ALMA-identified SMGs ($K_{\rm AB} \le$ 24) in 49 KMOS pointings across these three fields. These observations allow us to: 1) derive precise spectroscopic redshifts for the SMGs to measure their clustering and thus their halo masses; 2) study the dynamics and kinematics of ionised gas in a subset of $\sim$\,300 of the brightest SMGs to derive their dynamical masses and gas fractions; 3) compare SMG kinematics to less-active populations to test their triggering; 4) search for transition objects to probe the links between starburst and AGN at the era of peak activity of both populations. Near-infrared high-multiplex spectra from KMOS is the most efficient way to derive redshifts, spectral properties and dynamics (especially for the brighter examples at $z\leq$\,3--4) and thus understand SMG's place in the evolution of massive galaxies.




Current planet detection methods struggle to find planets around hot stars. Discovering planets in this regime would provide crucial information on how planet occurrence scales with stellar mass. Radial velocity surveys of evolved A-type stars hint that giant planets on $\sim$au orbits in this regime could be up to 5x more common than around solar-type stars. The only way to confidently detect these planets is via differential astrometry of sub-arcsecond early-type binary stars. Using data from a previous VLTI pilot test, we demonstrate that $\sim$10 micro-arcsecond precision can be achieved in 1-hour observations. This precision is sufficient to detect the ``wobble" of a star from 2-10 M$_J$ planets on $\sim$au orbits. Monitoring a sample of binaries for 2-years would reveal these planets, making this project perfectly suited for the large programme. The expert control of pupil and astrometric baseline with GRAVITY at VLTI are essential for controlling systematics that dominate the CHARA array, while better sensitivity at VLTI allows us to target wider binaries where planet suppression at 1 au is not expected. We propose to begin a large survey using GRAVITY and the ATs to monitor bright early-type binary stars in order to detect giant planets within a few au of individual stars in the binary pair. With 10 epochs on each of our sample of 30 targets, we expect to detect 8$\pm$3 giant exoplanets assuming a top-heavy distribution of planets.




One of the most exciting opportunities offered by GRAVITY is to directly resolve the broad line region (BLR) of active galactic nuclei using spectro-astrometry. Since P99 we have been exploiting this capability to study the inner workings of AGN in the K-band on unprecedented micro-arcsecond (sub-pc) spatial scales. We have made the first interferometric detection of the BLR and found ordered rotation in the quasar 3C 273 (GRAVITY collab., Nature, in press) proving both the feasibility and value of such measurements. This proposal takes a major step forward by extending this capability to measure BLR radius, structure, and kinematics for a sample of objects spanning four orders of magnitude in luminosity. We will establish a new, GRAVITY-based radius-luminosity relation, thereby testing reverberation mapping methods and forming the basis for more robust black hole mass measurements in large samples in the local and distant Universe. From the same data, we will simultaneously measure the size and structure of the hot dust ``torus'' to understand its origin and physical connection to the BLR. Our team of observers and theorists has extensive experience in AGN science including interferometry and reverberation. We have developed the analysis and modeling tools needed to fully capitalize on such a unique data set.




This VST monitoring program is part of an ongoing effort to measure $H_0$ to 1\% using the time delays in 40 strongly lensed quasars. This single-step technique needs no complex calibration and provides robust constraints on $H_0$. A 1\% measurement of $H_0$ will both clarify the current discrepancy in $H_0$ between CMB and local measurements with Cepheids and Supernovae and improve the FoM of any stage-IV survey by 40\%. In practice, we will carry out a high-cadence (daily) and high-SNR (1000) R-band monitoring to measure time delays in at least 6 systems to $<$2\% in 2 years, complementing our current monitoring with the MPIA 2.2m telescope. With the same VST data, we will build mass maps for each field with weak lensing, allowing to detect any mass clump along the lines-of-sights down to $\kappa_{ext}\sim0.02$. Together with existing and approved HST data, the VST time delays and weak lensing maps will add 6 new systems to the current H0LiCOW sample of 4 analyzed systems.




We propose to obtain several new MUSE Deep Fields of $t_{\mathrm{exp}} = 25^{\mathrm{h}}$ in blank-sky locations with ultra-deep HST multiband imaging and other ancillary data available. Our selected targets are the four parallel fields of the Hubble Frontier Fields legacy programme that are accessible to the VLT. Our observing strategy is guided by a combination of several science drivers: (1) Obtain spatially resolved spectroscopy of typical Lyman-$\alpha$ haloes at redshifts $z>3$, to constrain the physical nature of the halo gas and the dominant powering mechanism for the Ly$\alpha$ radiation. (2) Identify significant overdensities in the distribution of Ly$\alpha$ emitters and test previous claims that Lyman-$\alpha$ halo properties depend on the environment. (3) Build a statistically significant sample of galaxies out to $z\simeq 1$ for spatially resolved kinematic and dynamical analyses. These new observations will triple the number of MUSE Deep Fields, provide statistically independent locations to combat cosmic sample variance, and substantially improve in image quality over our previous deep fields efforts through the use of Ground-Layer Adaptive Optics. The new Deep Fields will be embedded in small mosaics of $2^{\mathrm{h}}$--$5^{\mathrm{h}}$ depth to mitigate edge effects, characterise the environments, and to increase the general legacy value of this survey by covering the full footprints of the HST images.




\veils, the VISTA Extragalactic Infrared Legacy Survey, is a current ESO Public Survey, covering 9 sqrdeg of extragalactic legacy fields with deep, cadenced observations. The innovative aspect of \veils\ is its design enabling the first wide-field $J$ and $Ks$-band extragalactic time domain survey. The goal of this time-domain survey is to use two independent standardisable candles -- type Ia supernovae and AGN dust time-lags -- to significantly improve constraints of cosmological parameters in a complementary way to BAO, weak lensing, or the CMB. In addition, we will search for new members of a recently discovered class of optically-elusive, infrared-bright transients. Progress on the transient and variability science goals of \veils\ has been compromised in the 2018 season by the low data quality and low completion rate of its optical support survey \textit{VOILETTE} (= VEILS OptIcal Lightcurves of Extragalactic TransienT Events). Here we want to use the opportunity of VIRCAM and OMEGACAM being available for another \veils\ observing season to make up for 2018 to successfully complete the science goals of the survey, i.e. (1) discover, classify, and build light curves of new type Ia supernovae, (2) monitor the optical variability of AGN to determine dust time lags, and (3) support identification of infrared transients with and without an optical counterpart.




An accurate measurement of the Hubble constant, H$_0$, is critical for the determination of all other cosmological parameters. The most recent determinations have revealed a 4.4$\sigma$ discrepancy between the local value of H$_0$, based on the distance ladder approach with Cepheid stars and type Ia supernovae, and the determination from the cosmic microwave background. If this holds up, then $\Lambda$CDM is not the complete model of the Universe. A measurement of the local H$_0$ which does not rely on the distance ladder represents a critical and independent check. We propose to use an extended version of the expanding photosphere method (EPM) of 12 type II-P supernovae to measure distances in the redshift range $0.04




The past 5 years have seen giant leaps in our understanding of circumstellar disks and planet formation. This is largely due to new capabilities of high spatial resolution observations in scattered light and mm-continuum emission. Where disks in previous decades were assumed to be smooth we now see that distinct features such as rings and spirals are ubiquitous. SPHERE is currently the best instrument worldwide to obtain scattered light observations of circumstellar disks. This has been done for many well known disks in the past few years. While scattered light observations of individual systems have produced spectacular results, we are missing out on the potential of unbiased disk surveys to probe the evolution of disk surfaces as ALMA surveys have done for the mid-plane. How is the appearance of a disk in scattered light linked to its evolutionary state? Are some features distinct signposts of planet formation? How does scattered light compare to dust continuum emission? All these are questions we want to answer with a dedicated survey of 85 young, nearby, disk-hosting stars. We in particular extend the parameter space to lower stellar masses and younger ages. Due to a new observation mode that was only recently commissioned we can now detect circumstellar disks and search for planets in the same systems simultaneously, making the proposed survey much more efficient than previous studies.




Galaxies have undergone dramatic dynamical, morphological and chemical evolution over the past $\sim$8 billion years. It is predicted that environment is a key driver of this evolution 4 billion years ago ($z\sim0.3$), when there was the greatest diversity of evolutionary pathways between satellites and centrals. However this critical epoch is beyond the reach of existing Integral Field Spectrograph (IFS) surveys. Current 3D spectroscopy of the \emph{stars and ionised gas} simultaneously has been limited to a short evolutionary window of $\lesssim 2$\,Gyr look-back time. \vspace*{0.1cm} To discern the drivers of galaxy transformation, we propose the \underline{M}iddle-\underline{A}ges \underline{G}alaxy \underline{P}roperties with \underline{I}ntegral Field Spectrograph (MAGPI) survey: a MUSE survey of 56 individual pointings to obtain spatially-resolved spectroscopy of stars and ionised gas for a representative sample of galaxies in a range of environments at 3--4\,Gyrs look-back time ($0.25 < z <0.35$). MUSE is the only instrument capable of building the large sample required to reveal the mechanisms responsible for the morpho-kinematic variety of today's massive galaxies. \vspace*{0.1cm} We bring together a strong and complementary team of experts from the high and low-redshift IFS communities (e.g.\ leaders of the SAMI and KMOS surveys) as well as theory and simulations experts to ensure that data and results are efficiently and meaningfully analyzed.




We propose to use 272 hours of VISTA time over the next 4 observing periods to complete and homogenize the ultra-deep $Y$-band imaging provided by the UltraVISTA survey over the full 1.5 $\times$ 1.2 deg VIRCAM field-of-view. To ensure a realistic achievable observing schedule, we will interleave this $Y$-band imaging with existing approved UltraVISTA $J$,$H$ and $K_s$ imaging in the COSMOS field, to complete the final UltraVISTA observing by summer 2021, and the final public legacy data product by summer 2022 (when the complete Subaru Hyper Suprime-Cam (HSC) deep imaging of the field at shorter wavelengths will also be public). This last additional investment in UltraVISTA only extends the survey by just over one year, but will: {\bf i)} deliver a complete and coherent legacy dataset, {\bf ii)} double the area in the field available for searches for luminous Lyman-break galaxies at $z \simeq 7- 8$ (for follow-up with {\it JWST}), {\bf iii)} enable us to take advantage of the subtle differences between the VIRCAM $Y$-band and HSC $y$-band filters to estimate the prevalence of Ly-$\alpha$ emission from galaxies at $z \simeq 7$ (a key indicator of the progress of cosmic hydrogen reionization), {\bf iv)} improve the accuracy of photometric redshifts in the COSMOS field across a broad range of cosmic time, and significantly enhance the already recognised value of the COSMOS/UltraVISTA field as a key calibration field for the {\it Euclid} Deep Survey.




Combining adaptive optics and interferometric observations results in a considerable contrast gain compared to single-telescope, extreme AO systems. Taking advantage of this, we propose VLTI/GRAVITY observations of all known young giant exoplanets located in the range of 0.1'' to 2'' from their stars. The observations will provide astrometric data of unprecedented accuracy, being crucial for refining the orbital parameters of planets and illuminating their dynamical histories. Furthermore, GRAVITY will measure non-Keplerian perturbations due to planet-planet interactions in multi-planet systems and directly measure masses. Over time, repetitive observations of the exoplanets at medium resolution (R=500) will provide a catalogue of K-band spectra of unprecedented quality, for a number of exoplanets. The K-band has the unique properties that it contains many molecular signatures (CO, H2O, CH4, CO2). This allows constraining precisely surface gravity, metallicity, and temperature, if used in conjunction with self-consistent models like Exo-REM. Further, we will use the parameter-retrieval algorithm petitRADTRANS to constrain the C/O ratio of the planets. Ultimately, we will produce the first C/O survey of exoplanets, kick-starting the difficult process of linking planetary formation with measured atomic abundances.




This VST monitoring program is part of an ongoing effort to measure H0 to 1% using the time delays in 40 strongly lensed quasars. This single-step technique needs no complex calibration and provides robust constraints on H0. A 1% measurement of H0 will both clarify the current discrepancy in H0 between CMB and local measurements with Cepheids and Supernovae and improve the FoM of any stage-IV survey by 40%. In practice, we will carry out a high-cadence (daily) and high-SNR (1000) R-band monitoring to measure time delays in 6 systems to <2% in 1 year, complementing our current monitoring with the MPIA 2.2m and VST telescopes. With the same VST data, we will build mass maps for each field with weak lensing, allowing to detect any mass clump along the lines-of-sights down to ?_ext~0.02. Together with existing and approved HST data, the VST time delays and weak lensing maps will allow us to terminate our program by meeting our final goal of 40 time-delay lenses.




High-fidelity spectroscopy and high-precision radial velocities are an essential technique to obtain accurate planetary masses, radii and densities, while also enabling for the atmospheric characterization of these planets. We pursue one of the main science goals of the ESPRESSO GTO: the detection and characterization of Earth-mass planets (possibly) inside the habitable zone of G, K and M stars. We address it with 3 sub-programs: (1) An intensive search for habitable rocky planets in a sample of the most suitable stars ? some of which already hosting planets ? in the solar neighbourhood. (2) A survey for exoplanetary atmospheres through transit and reflected-light spectroscopy, exploiting the unique spectroscopic capabilities of ESPRESSO and the collecting area of the UTs. (3) A follow-up of the most challenging, low-mass planetary candidates from K2 and TESS missions to obtain their precise densities. This proposal covers the third year of ESPRESSO GTO (exoplanetary case).




Herschel imaging surveys of nearby clouds (d < 0.5 kpc) support a filament paradigm for low-mass star formation (SF), whereby Jeans-type fragmentation of 0.1-pc wide supercritical filaments produces < 0.1pc prestellar cores, which then collapse to core-fed protostars. There is mounting evidence, however, that massive prestellar cores may not exist and that high-mass protostars may be clump-fed, gathering mass from parsec-scale hub-filament systems. We propose to use ArT�MiS on APEX, which provides 3.5 times better resolution than Herschel at 350/450 ?m, to achieve, for the first time, an essentially complete survey of the structure of the densest (Av > 40) molecular gas at < 0.1 pc resolution out to d ~ 3 kpc (total survey area ~5.5 deg^2). We wish to i) investigate whether fragmentation of 0.1-pc wide filaments remains the dominant mode of SF beyond the Gould Belt, and ii) clarify where/how the transition between a core-fed and a clump-fed regime of protostellar mass growth occurs.




We pioneered the use of integral-field spectrographs as multi-object facilities to determine the internal kinematics of globular clusters (GCs) from the radial velocity of resolved stars. The preliminary results are striking: we found hints of central velocity dispersion cusps and drops (possibly indicating intermediate-mass black holes and disk-like sub-structures, respectively) and rotating cores kinematically decoupled from the rest of the cluster. The enhanced performances of MUSE/NFM finally enable the optimal kinematical exploration of GC cores at sub-arcsecond scales, allowing to properly address these exciting issues. We propose a Large Programme with MUSE/NFM to determine the velocity dispersion and rotation profiles in the innermost 10" of a selected sample of 18 high-density GCs. The proposed observations promise breakthrough discoveries in the field of stellar dynamics, and to set the new paradigm for the correct understanding of the physics of collisional stellar systems.




We propose a 275hr VIRCAM Ks medium-deep survey of the Euclid Deep Field South Field (EDFS). The ~20 deg^2 area covered by EDFS is a region close to the south ecliptic pole already observed with Spitzer at 3.6 and 4.5 mu. In this field, Euclid deep observations will provide high spatial-resolution near-IR imaging (Y, J, and H), while the Vera Rubin Observatory (VRO) will deliver optical images of comparable depth. The field is also in the continuous viewing zone of WFIRST and JWST. The proposed Ks band VIRCAM observations will significantly straddle the wide wavelength gap between the Euclid and the Spitzer data. The proposed observation will secure long-lasting legacy data and will enable broad range of science cases. They will allow to address key questions like the nature and statistics of UltraMassive Passive Galaxies and high redshift galaxy clusters studies. Forthcoming VIRCAM decommisioning will make EDFS Ks band observations unfeasible with any other telescope.




The Transiting Exoplanet Survey Satellite (TESS) has ushered in a new era in which it is finally possible to study the composition of small exoplanets for several dozen systems. This is because TESS has discovered hundreds of new transiting planets orbiting the nearest and brightest stars over the last two years, which are thus suitable for high-precision radial velocity observations. The KESPRINT consortium has seized this opportunity by characterizing ~25 TESS planets, in terms of mass, radius, and orbital parameters. Here, we seek to extend and expand our HARPS program by doubling the sample of precisely characterized small planets, leading to a total of 70 planets for which the mass will be known with a precision better than 15%. This enhanced sample will allow us to conduct precise comparative planetology by providing reasonably good number statistics for the first time, as well as extending to longer orbital periods and a wider range of stellar parameters than ever before.




Spectroscopic Lyman-alpha (Lya) observations have transformed our view of the early universe, and in particular at the epoch of reionization (EoR). Lya emission is one of the few currently accessible tracers of the shapes and sizes of ionized bubbles, but contemporary efforts are limited to a handful of heterogeneous, luminous, and unrepresentative systems, that carry no statistical power. Here we propose the next generation of Lya reionization surveys: an ambitious large program to obtain extremely deep, high-resolution spectra of 350 ordinary Lya-emitting galaxies with FLAMES/MEDUSA, that will provide a high-fidelity view of the z>6 intergalactic medium on Mpc scales. We will measure the IGM opacity and size distribution of ionized regions at unprecedented precision, and characterize its dispersion and redshift evolution. The program is highly optimized (<22 min/galaxy), and the unique atlas will provide revolutionary new EoR measurements that will last well into the ELT era.




The low metallicity (Z) Universe is fundamentally different from the present-day Milky Way. We know this from observations of individual massive stars, superluminous supernovae, gamma-ray bursts, and more recently from gravitational wave events involving spectacular Black Hole Mergers that will remain obscure until we gain a firm understanding of the physics & evolution of massive stars at low Z. For this reason, a large number of HST orbits have been dedicated to ULLYSES to build an ultraviolet (UV) spectral library of massive stars at low Z. However, without the complementary optical and near infrared (NIR) spectroscopy the real promise of the ULLYSES dataset is anticipated to remain limited. For this reason, the massive-star community proposes to bring true Legacy value by including not only the critical optical range for stellar parameter determination, but also the NIR regime for future benchmarking purposes, both uniquely offered by X-Shooter in one single shot.




A new generation of wide-field sky surveys, some monitoring the sky several times per night, mean we are now in a golden era of transient astronomy. Gathering the ESO community working on supernovae (SNe) and unusual transients into one coherent team, we have revolutionised the exploitation of these surveys, developing efficient synergies with multi-messenger experiments and making the NTT a crucial global facility (100+ papers). We have provided legacy datasets for the electromagnetic counterpart of gravitational waves, the lowest metallicity supernovae, the fastest evolving transients, long-lived supernovae not explained by standard neutrino-driven explosions, as well as unveiled a diversity in the most luminous supernovae. We now propose to continue such spectroscopic follow-up, building on the success of our PESSTO consortium and bridging the gap to the SOXS instrument that will arrive at the NTT in 2021. We will continue to make all reduced data public as we have done so far.




Gamma-ray bursts (GRBs) are the most violent and luminous explosions known in the universe, and drive ultra-relativistic jets shocking the surrounding medium. The evolution of their broadband SEDs and polarisation offer a unique laboratory for exploring physics under these extreme conditions. Their bright afterglows provide ideal backlights for exploring gas in the host and IGM. We propose a multi-faceted, long-term campaign of rapid follow-up bringing together all current users of ESO for GRB observations. The primary goals are: studying short GRBs, thought to be produced by compact object binary mergers that also produce gravitational waves; characterising early galaxies through spectroscopy of long GRBs at z>~6; identifying and performing novel investigations of the brightest and most exceptional events; and enabling statistical studies of enhanced samples. ESO facilities have a key role, and our coordinated strategy aims to maximise efficiency and science return.




Planets orbiting both stars of a binary system -circumbinary planets- are challenging our understanding about how planets are assembled and how their orbits subsequently evolve. We aim to assess how similar and how different the orbital and physical properties of circumbinary planets are to the properties of planets orbiting single stars. Only twelve binary systems are currently known to host circumbinary planets. However, HARPS radial-velocities collected in the past two years have revealed the presence of circumbinary planet candidates in 15 new systems. With this proposal, we request time on HARPS to confirm 15 planetary candidates which can double the total number of known circumbinary systems. We will also search for longer period and lower mass planets on 20 stable systems, and will monitor a sub-sample of 10 bright new binaries identified by TESS and KELT for new candidates.




The evolution of young stars and disks is driven by the interplay of several processes, notably accretion and ejection of material. Critical to correctly describe the conditions of planet formation, these processes are best probed spectroscopically, using the fluxes and profiles of emission lines, and the UV to IR continuum emission shape. HST will devote 500 orbits in 2020-2022 to the ULLYSES public survey of 82 low-mass (M ? 2Msun) young (age<10 Myr) stars at UV wavelengths. These UV spectra will be a unique possibility to have for the first time a comprehensive view of the accretion/ejection processes ONLY IF they will be combined with contemporaneous high-resolution and flux-calibrated optical to near-IR spectra. We propose to create an unprecedented dataset with contemporaneous ESPRESSO/UVES spectra to spectrally resolve the kinematics of lines, and X-Shooter flux-calibrated spectra to derive extinction, stellar properties, and the fundamental parameters that HST cannot provide.


Send comments to <opo@eso.org>
Last update: OPO - August 4, 2020