Catalyst Rubin-LSST post-doc fellowship proposals

Abstract:

Astronomical data-sets are rapidly growing both in size and complexity: current and future surveys, such as the Vera C. Rubin Observatory Legacy Survey of Space and Time (Rubin-LSST), will generate an unprecedented amount of data, far beyond the feasibility of human review and analysis. Automatic tools are thus needed in order to extract information hidden in these wide data-sets. Rare, high-redshift AGN are examples of gems awaiting to be dug out from the billions of galaxies and stars that will be observed by Rubin-LSST. The proposed project aims at using state-of-the-art machine learning techniques (e.g. CCA, PRF, XGB) to identify such high-z AGNs using LSST and future available photometric catalogs, looking for the needles in the haystack. The multi-wavelength coverage of the LSST survey, combined with its extreme depth and a real coverage, will allow us to have an unprecedented database of AGN. The unique LSST catalog will also be extremely important to test and train the top-level machine learning algorithms we are currently applying with great success on much shallower databases (e.g. Skymapper, PanSTARRS). The computational challenges of handling the multi-Petabyte LSST data-set will be further complicated by the addition of future data-bases (e.g. Euclid, Roman Space Telescope), thus the proposed work will have fundamental future applications which will allow us to obtain transformational results in the field of high-z AGN, cosmology, and fundamental physics.

Site:

The hosting site will be unique and the candidate could choose the site for his work among the INAF departments of Bologna, Roma, Pisa, Padova or Trieste. The work will be in collaboration with the researchers from those different sites.

P.I. & Contact Person:

Andrea Grazian (INAF - Osservatorio astronomico di Padova)

Participants:

• A. Bongiorno (INAF - Osservatorio astronomico di Roma)

• K. Boutsia (Carnegie/Las Campanas Observatory)

• S. Cristiani, G. Cupani, V. D’Odorico, G. Calderone, F. Guarneri (INAF - Osservatorio astronomico di Trieste)

• R. Decarli, M. Mignoli, V. Allevato (INAF - Osservatorio di Astrofisica e Scienza dello spazio di Bologna)

• S. Gallerani (Scuola Normale Superiore, Pisa)

Collaboration with other programs:

• Euclid

• LISA

Access to further facilities:

• NTT

• TNG

• VLT

• Magellan

• LBT

LSST Science Collaborations Involved:

• AGN

Abstract:

Since the discovery that AGN and galaxy evolution are strongly connected, obtaining a complete census and characterization of the AGN population has become a priority of the astronomical community. The Rubin Observatory Legacy Survey of Space and Time (LSST) will tackle this problem through its extensive sky coverage, multi-band observations and monitoring strategy. Variability, combined with optical colors, is the main method envisioned to select and study AGN; reverberation mapping on 10–1000 days timescales will further allow to derive masses for thousands of AGN. However the lack of studies exploiting variability selection with monitoring cadence, baselines, and depths comparable to LSST, makes difficult to characterize its expected efficiency, the AGN selection function and contamination. This will limit our ability to constrain the properties and evolution of the millions of AGN that LSST will discover, especially in the first years of operation. We propose to use existing archival surveys on the Deep Drilling Fields (DDF), where plenty of ancillary multiwavelength observations are available, to characterize the LSST performance for AGN studies, extend its temporal baseline, and allow the exploitation of LSST data from the very beginning of the survey, creating the training sets for the rest of the survey and for Machine Learning algorithms. Our group has extensive experience in the study of AGN variability through wide survey. We have access to archival public data (HSC, VST, DES etc.) as well as proprietary VST monitoring data covering the LSST DDFs (COSMOS, W-CDFS-S, ELAIS-S1). We intend to study the variability properties of all classes of AGNs including the debated link between variability, BH mass and accretion rate, improving the identification of low- luminosity, Type-2, and peculiar AGN requiring long monitoring baselines.

Site:

INAF - Osservatorio Astronomico di Capodimonte in collaboration with Università degli studi di Napoli Federico II

P.I. & Contact Person:

Maurizio Paolillo (Università degli studi di Napoli Federico II)

Participants:

• S. Cavuoti, M. Brescia, F. Ragosta, M.T. Botticella, N. Napolitano, E. Iodice, M. Spavone (INAF - Osservatorio astronomico di Capodimonte)

• M. Radovic (INAF - Osservatorio astronomico di Padova)

• O. Torbaniuk, G. Covone, V. Petrecca (Università degli studi di Napoli Federico II)

• N. Brandt (Penn State University)

• D. De Cicco, F. Bauer (Univ. Catolica de Cile)

• G. Pignata (Univ. Andres Bello de Cile)

• M. Vaccari (University of the Western Cape South Africa)

Collaboration with other programs:

• VST GTO surveys on ELAIS-S1, VEGAS, W-CDF-S

Access to further facilities:

• VST-Omegacam and GTO programs

• Euclid

• Università degli studi di Napoli Federico II and INAF computing facilities

LSST Science Collaborations Involved:

• AGN

• Transients/variable stars

Abstract:

Clusters of galaxies are the nodes of the cosmic web, constantly growing through accretion of matter along filaments or mergers. They are excellent laboratories to study the physics of the gravitational collapse, and the non-gravitational physics that affects their baryonic components. As cluster growth and evolution depend on the underlying cosmology, they are powerful cosmological probes. Many questions are still to be answered: What is the cluster mass scale? How does the formation process inform the equilibrium state of clusters? What are the statistical properties of the cluster population?

These questions can be answered in the context of large surveys, where clusters play the role of the ultimate products of structure formation in time and mass.

The research program will take place at the INAF Observatory of Astrophysics and Space Science. Bologna is a lively city and an excellence centre for astrophysics in Europe with a campus hosting four, tightly connected institutes: INAF-OAS, INAF Radio Astronomy Institute (IRA), the Department of Physics and Astronomy (DIFA) of the University of Bologna (UNIBO), and the Cherenkov Telescope Array (CTA) headquarters.

The Galaxy Cluster Science group has leading roles in (optical, lensing, X-ray, SZ) data analysis, theoretical interpretation, modelling, and numerical simulation of the structure and distribution of galaxy clusters, mostly in the context of major international programs, such as Rubin-LSST, Euclid, CHEX-MATE, KiDS and XXL . High performance computing is supported by in-site facilities.

Site:

INAF - Osservatorio di Astrofisica e Scienza dello spazio di Bologna

P.I. & Contact Person:

Mauro Sereno (INAF - Osservatorio di Astrofisica e Scienza dello spazio di Bologna)

Participants:

• M. Baldi, L. Moscardini (Università di Bologna)

• S. Ettori (INAF - Osservatorio di Astrofisica e Scienza dello spazio di Bologna)

Collaboration with other programs:

• Euclid Clusters of Galaxies Science working Group

• CHEX-MATE (Cluster HEritage project with XMM-Newton - Mass Assembly and Thermo-dynamics at the Endpoint of structure formation)

• KiDS (Kilo-Degree Survey)

• XXL

LSST Science Collaborations Involved:

• Dark Energy

Abstract:

INAF-Capodimonte, INAF-Padova and DARK are happy to support a Templeton Fellow working on gravitational lensing and galaxy clusters. The researcher will develop new, open-source software to perform the most complete and realistic models of gravitational lensing by galaxy clusters, which can incorporate deep imaging information from RubinLSST. This work will allow the researcher and the whole community to exploit all available information about galaxies to deploy the most flexible, yet accurate, collimation of galaxy clusters as cosmic telescopes. Current models are still too simplistic in their description of the gravitational potential of individual cluster-member galaxies, and a significant software refactoring effort is required in order to produce models worthy of LSST imaging quality. The new models will extend the hierarchical inference introduced in the publicly available BayesLens, to include more realistic models of individual cluster-member galaxies. DARK can offer computational support through its own HPC cluster and two desktop servers, as well as an established mentoring program.

Site:

INAF - Osservatorio Astronomico di Capodimonte in collaboration with Niels-Bohr Institute (DARK)

P.I.:

Enrica Iodice (INAF - Osservatorio Astronomico di Capodimonte)

Contact Person:

Adriano Agnello (Niels-Bohr Institute)

Participants:

• C. Tortora (INAF - Osservatorio Astronomico di Capodimonte)

• B. Vulcani, A. Zanella (INAF - Osservatorio Astronomico di Padova)

• J. Hjorth (Niels-Bohr Institute)

LSST Science Collaborations Involved:

• Dark Energy

• Strong Lensing

Abstract:

INAF-Capodimonte, INAF-Padova, Oxford and DARK are happy to support a Templeton Fellow working on data visualization. The researcher will build new, scalable, visualisation tools and AR/VR software to navigate the deep and sharp images from Rubin-LSST. These project will also result in visual inspection tools that are useful to astrophysicists, but it will also produce public, high-definition images of the night sky for planetarium and wider outreach initiatives, also in collaboration with local artists at the three co-host institutions. While its more technical scope is the production of efficiently compressed catalogs and images (e.g. for the guiding systems of extremely large telescopes), it has wider societal implications in bringing the general public closer to the stunning and panchromatic view of the night sky that is made possible by the Rubin-LSST. The researcher can rely on computational resources through DARK, contact with outreach specialists and local artists, an established mentorship program, and a truly international environment thanks to the collaboration of three hosts (OAC, Oxford, DARK-NBI) and the European Southern Observatory.

Site:

INAF - Osservatorio astronomico di Padova in collaboration with Niels-Bohr Institute (DARK), Oxford University.

P.I. & Contact Person:

Anita Zanella (INAF - Osservatorio astronomico di Padova)

Participants:

• B. Vulcani (INAF - Osservatorio astronomico di Padova)

• C. Spiniello (INAF - Osservatorio astronomico di Capodimonte, Oxford University)

• J. Hjorth (Niels-Bohr Institute)

• L. Izzo (INAF - Osservatorio astronomico di Capodimonte, Niels-Bohr Institute)

LSST Science Collaborations Involved:

• Dark Energy

• Stars, Milky Way, and Local Volume

• Transients/variable stars

Abstract:

A full understanding of galaxy mass assembly, star formation histories (SFHs), and the role of the environment on galaxy morphology and stellar populations is still lacking. With deep surveys at high spatial resolution on the widest possible sky area, Rubin and Euclid will overcome this gap, through an exquisite characterization of the resolved and partially resolved stellar populations in the Local Universe.

The unique wavelength coverage of the Rubin + near-infrared Euclid combination will open a new window on the “stellar backbones” of galaxies and on SFHs, mitigating the stellar population parameter degeneracies inherent in fitting spectral energy distributions (SEDs) or in analyzing colour magnitude diagrams (CMDs) for resolved stellar populations. This powerful combination of multi-wavelength information, resolution and depth is ideal to fully exploit the pixel level feature extraction to constrain stellar populations, developing new approaches based on deep learning (e.g., Bonjean et al. 2019; Delli Veneri et al. 2019). It will be possible to compare them with more classical SED fitting techniques (e.g. Abdurro’uf et al. 2021), and will soften the boundaries between resolved stellar populations and partially-resolved ones, enabling pixel-based CMDs (e.g. Conroy & van Dokkum 2016) and capturing the full potentiality of this technique using maching learning.

The work proposed in PASTEL-RED will be executed at the Capodimonte Astronomical Observatory in Napoli, under the supervision of Crescenzo Tortora (co-lead of a Work Package on stellar populations in the Local Universe within the Euclid Consortium), counting on the tight collaboration with experts in stellar populations, SED fitting and machine learning, involved (and with leading roles) within the Rubin and Euclid Collaborations.

Site:

INAF Osservatorio Astronomico di Capodimonte

P.I. & Contact Person:

Crescenzo Tortora (INAF - Osservatorio Astronomico di Capodimonte)

Participants:

• M. Bolzonella (INAF - Osservatorio Astronomico di Bologna)

• M. Brescia, S. Cavuoti (INAF - Osservatorio Astronomico di Capodimonte)

• L. Hunt (INAF - Osservatorio Astrofisico di Arcetri)

Collaboration with other programs:

• Euclid Consortium (in particular the Local Universe SWG, Galaxy evolution and AGN SWG, OU-PHZ)

LSST Science Collaborations Involved:

• Galaxies

Abstract:

The LSST project will discover thousands of new multiply imaged quasars and supernovae (Oguri & Marshall 2010). By exploiting available HST and VLT observations and future LSST data, we will develop detailed cluster strong lensing models and transform time delays in lens galaxy clusters into a fundamental alternative tool for measuring the expansion rate and the geometry of the Universe. We will combine the measured time delays between the multiple images of variable or transient background sources and the observed positions of the multiple images of lensed galaxies to infer the values of cosmological distances at different redshifts. By combining the independent estimates from ~10 strong lensing studies, we will achieve the ambitious goal of a complementary and competitive measurement of the value of H0 with a 2% uncertainty. We have recently demonstrated the feasibility of this long-term goal using high-quality spectro-imaging data and high-precision strong lensing modelling on the multiply imaged supernova “Refsdal”. Within the LSST Collaborations, we will select the best targets, making use of data mining and model-based selection techniques. The international team has years of experience in the analysis of optical data and in the modelling of strong lenses. Time delay cosmography is based on well-known physics (General Relativity) and is a single-step technique, without any complex calibration. This study will help clarify whether the current, hotly debated tension on the value of H0 must be ascribed to intriguing new physics or to significant systematic effects, and improve by 40% the Figure of Merit of any stage-IV cosmological survey (LSST, Euclid, etc.).

Site:

Istituto di Astrofisica Spaziale e Fisica cosmica di Milano in collaboration with Università degli Studi di Milano, Department of Physics

P.I. & Contact Person:

Claudio Grillo (University of Milan, INAF - Istituto di Astrofisica Spaziale e Fisica cosmica di Milano)

Participants:

• A. Mercurio, M. Brescia (INAF - Osservatorio astronomico di Capodimonte)

• C. Carbone (Istituto di Astrofisica Spaziale e Fisica cosmica di Milano)

• C. Giocoli, M. Meneghetti (INAF - Osservatorio di Astrofisica e Scienza dello spazio di Bologna)

• M. Nonino (INAF - Osservatorio astronomico di Trieste)

• P. Rosati (University of Ferrara, INAF - Osservatorio di Astrofisica e Scienza dello spazio di Bologna)

• G. Caminha, S. Suyu (Max-Planck-Institut fuer Astrophysik, Technische Universitaet Muenchen)

LSST Science Collaborations Involved:

• Strong Lensing

• Dark Energy

• Galaxies

• AGN

• Transients/variable stars

Abstract:

The project aims at developing and calibrating a tool to determine stellar parameters and metallicity from Rubin/LSST photometry. Spectroscopic metallicities from Gaia-ESO Survey and from other public large spectroscopic surveys (e.g., APOGEE, GALAH, LAMOST) will be used to build a large database of stellar parameters, metallicities and individual abundances. The results of spectroscopic surveys, which will be constantly updated considering also forthcoming surveys to which we participate, will be used to build up relationships to convert the photometric colours in estimates of stellar parameters and metallicity, [Fe/H] and [alpha/Fe]. The creation of a metallicity map from the fields observed by Rubin/LSST will open wide horizons for the study of the formation and evolution processes of our Galaxy, such as the identification and study of stellar streams and remnants of past mergers, and for the detection of radial, vertical, and azimuthal variations in the thin and thick disks, and in the halo. The postdoc fellow will benefit from the international collaborations within large spectroscopic surveys of which we are part: Gaia-ESO, WEAVE, MOOS and 4MOST.

Site:

INAF - Osservatorio Astrofisico di Arcetri

P.I. & Contact Person:

Laura Magrini (INAF - Osservatorio Astrofisico di Arcetri)

Participants:

• G. Sacco (INAF - Osservatorio Astrofisico di Arcetri)

Collaboration with other programs:

• Gaia-ESO

• WEAVE

• MOONS

• 4MOST

LSST Science Collaborations Involved:

• Stars, Milky Way, and Local Volume

Abstract:

The Padova Observatory and its neighbouring Department of Astronomy of the University of Padova host a research team dedicated to stellar evolution and stellar population models, which is now preparing for the vibrant era of discovery to be open by Rubin-LSST. Current research concentrates on aspects such as developing calibrated models of asymptotic giant branch stars and their chemical sub-types, understanding the period-luminosity relation of long-period variables, unveiling the frequency of rapidly-rotating stars in clusters and nearby galaxies, mining the Gaia catalogue for close binaries and their progeny, calibrating stellar ages through asteroseismology, documenting the variability of hot stars in globular clusters and in the field, deriving star formation histories in Local Group galaxies, etc. The team preparing for LSST includes Leo Girardi, Simone Zaggia, Yazan Momany, Paola Marigo and about 10 PhD students and postdocs. We also have a wide and dynamic network of international collaborations (we advise a search through ADS to identify the most active ones), and participate in a few large Local Group surveys such as VMC+VMCdeep, PHAT+PHATTER+PHAST, WINGS, etc. We will be glad to host "Catalyst LSST/Rubin" postdocs to work on any of these areas, and even more if the planned research involves using our stellar population codes and tools (PARSEC, COLIBRI, TRILEGAL, TRIMCMC, etc.), and photometry pipelines. The candidates will be hosted at the Padova Observatory and will be expected to work with either one or both the SMWLV and TVS Science Collaborations.

Site:

INAF Osservatorio Astronomico di Padova

P.I. & Contact Person:

Leo Girardi (INAF - Osservatorio astronomico di Padova)

Participants:

• S., Zaggia, Y. Momany, P. Marigo (INAF - Osservatorio astronomico di Padova)

• about 10 PhD students and postdocs (INAF - Osservatorio astronomico di Padova)

LSST Science Collaborations Involved:

• Stars, Milky Way, and Local Volume

• Transients/variable stars

Abstract:

INAF-Capodimonte, INAF-Padova, Oxford and DARK are happy to support a Templeton Fellow working on transients. The researcher will exploit the depth of Rubin-LSST depth to discover elusive nearby galaxies (d <~ 10 Mpc) thanks to low- and intermediate luminosity transients (g_abs >~ -12 mag), including novae, luminous red novae, ILOT, and study their local rate, which varies widely with the host properties and are still poorly characterised. The goal is the development of new algorithms to find these transients and especially their faint host galaxies, thanks to real-time alerts from the LSST. The researcher will also have access to LSST stacked images, to spot nearby faint dwarf galaxies once high-confidence transients are identified. Our experience with the Young Supernova Experiment provides a wealth of preparatory data, infrastructure and experience for the development of the project. The researcher will also have access to the Danish 1.5 meter telescope in La Silla and other observational facilities. This project is co-hosted at INAF-OAC and DARK-NBI, in order to capitalize on: access to a large International Data Access Centre (based in Denmark), access to proprietary telescopes and international collaborations, and reach out to traditionally underserved communities in Denmark and Southern.

Site:

INAF - Osservatorio astronomico di Capodimonte in collaboration with Niels-Bohr Institute (DARK)

P.I.:

Massimo Della Valle (INAF - Osservatorio astronomico di Capodimonte)

Contact Person:

Luca Izzo (Niels-Bohr Institute & INAF - Osservatorio astronomico di Capodimonte)

Participants:

• M. T. Botticella (INAF - Osservatorio astronomico di Capodimonte)

• B. Vulcani, A. Zanella (INAF - Osservatorio astronomico di Padova)

• C. Angus, A. Agnello, J. Hjorth (Niels-Bohr Institute)

• C. Spiniello (Oxford University & INAF - Osservatorio astronomico di Capodimonte)

• S. Lombardo (Laboratoire d'Astrophysique de Marseille)

Collaboration with other programs:

• Young Supernova Experiment

• CASTLE

• SOX

Access to further facilities:

• Nordic Optical Telescope

• Danish 1.5m Telescope

• Pan-STARRS1/2 surveys

• CASTLE

• VST

• Telescopio Nazionale Galileo

LSST Science Collaborations Involved:

• Stars, Milky Way, and Local Volume

• Transients/variable stars

Abstract:

INAF-Capodimonte and DARK are happy to support a Templeton Fellow working on transients and discovery pipelines. The researcher will develop new algorithms for the prioritisation and follow-up of transients from Rubin-LSST alerts. Possible directions include: new complete catalogs of galaxies in the nearby Universe to identify faint transient hosts; new prioritisation and pre-classification algorithms; fully automated pipelines to plan the immediate multi-epoch photometry and low-resolution spectroscopy follow-up at supporting telescopes and the design of new instrumentation for the follow-up itself. Through this co-hosted project, the researcher will have access to: the Danish 1.5m telescope (owned by NBI), whose spectroscopic capabilities are currently being refurbished; computational support through DARK’s own HPC cluster and two desktop servers; access to the Young Supernova Experiment, for preparatory work; and an established mentoring program and a truly international environment spanning multiple countries.

Site:

INAF - Osservatorio astronomico di Capodimonte in collaboration with Niels-Bohr Institute (DARK).

P.I.:

Massimo Della Valle (INAF - Osservatorio astronomico di Capodimonte)

Contact Person:

Luca Izzo (Niels-Bohr Institute & INAF - Osservatorio astronomico di Capodimonte)

Participants:

• A. Agnello, C. Angus, C. Gall, J. Hjorth (Niels-Bohr Institute)

Collaboration with other programs:

• Young Supernova Experiment

LSST Science Collaborations Involved:

• Stars, Milky Way, and Local Volume

• Transients/variable stars

Abstract:

INAF-Padova and DARK are happy to support a Templeton Fellow working on space debris. The researcher will be in a prime position to develop new techniques to identify the faint signatures of small-scale debris and reconstruct orbits for subsequent tracking. Thanks to the depth and image quality of the Rubin-LSST, this research can bridge the gap between small objects identified with radar technology and larger objects that are identified with fast but small optical telescopes. New techniques will need to be developed on purpose, due to the longer integration times of LSST exposures. The researcher can rely on nightly data and computational support from the Young Supernova Experiment for preparatory work, and contact with space agencies to ingest public data on the tens of thousands of objects that are already being tracked. Collaborations with amateur astronomer associations will be initiated through outreach initiatives and active follow-up of candidates. NBI, IDA and DTU have ongoing “environment change” programs and can initiate contact with space agencies. DARK also has an established mentoring program.

Site:

INAF - Osservatorio astronomico di Padova in collaboration with Niels-Bohr Institute (DARK).

P.I.:

Benedetta Vulcani (INAF - Osservatorio astronomico di Padova)

Contact Person:

Adriano Agnello (Niels-Bohr Institute)

Participants:

• J. Hjorth (Niels-Bohr Institute)

• L. Izzo (INAF - Osservatorio astronomico di Capodimonte, Niels-Bohr Institute)

Collaboration with other programs:

• Young Supernova Experiment

LSST Science Collaborations Involved:

• Solar System

Abstract:

The breakthrough detection of the binary neutron star merger GW170817 in both gravitational and electromagnetic waves opened a new window in multi-messenger astronomy, demonstrating a transformative potential for astrophysics and fundamental physics. While many more GW events are anticipated in the next few years, the discovery and multi-wavelength follow up of their counterparts is a challenging endeavor for current facilities and strategies. The Rubin-LSST is the perfect machine to search for light from compact binary mergers, thanks to its wide field of view and exquisite sensitivity. This project sets in the broad context of exploiting joint detections to answer fundamental questions spanning from nuclear matter physics, cosmology and high energy astrophysics. In the last two decades the INAF-OABrera played a leading role in the field. Our team major achievements on GW170817 were: (i) the spectroscopic characterization (with the Xshooter/VLT) of the kilonova (Pian, D’Avanzo et al. 2017) (ii) the characterization of the jet emission with XMM-Newton (D’Avanzo et al. 2018) (iii) the measurement of the source size and confirmation of proper motion through radio VLBI (Ghirlanda et al. 2019). The research environment at INAF-OABrera offers the candidate full access to national (GRAWITA; PROMETEO) and international (ENGRAVE) collaborations for the search and characterization of the electromagnetic counterparts (GRB, kilonova and jet afterglow) of compact mergers. Team members are also part of the LIGO/Virgo/KAGRA collaboration which guarantees full realtime access to the GW detection and data products. Approved observing programmes at the major national (TNG, SRT) and international (Swift, VLT, EVN) facilities guarantees to the project full support to characterise, in concert with LSST data, these transients. The candidate work will be supported also by computing resources (CINECA) and cloud computing (Amazon clusters) available through dedicated calls.

Site:

INAF - Osservatorio Astronomico di Brera

P.I. & Contact Person:

Giancarlo Ghirlanda (INAF - Osservatorio Astronomico di Brera)

Participants:

• M.G. Bernardini, S. Campana, P. D’Avanzo, A. Melandri, G. Ghisellini, G. Tagliaferri, L. Nava, S. Covino (INAF - Osservatorio astronomico di Brera)

Collaboration with other programs:

• GRAWITA

• PROMETEO

• LIGO/Virgo/KAGRA

• STARGATE

• ENGRAVE

LSST Science Collaborations Involved:

• Transients/variable stars

Abstract:

The Rubin Observatory’s Legacy Survey of Space and Time (LSST) will discover millions of new stellar transients in different time domains and with different evolutionary time scales. We are interested in studying multiple types of intermediate-luminosity optical transients, including fast-evolving stripped envelope supernovae (SNe), SN impostors, stellar mergers, along with very luminous SNe (pair-instability events, magnetar-powered SNe, SNe interacting with their circum-stellar environments). Non-terminal explosive events such as SN impostors (mostly giant eruptions of luminous blue variables) will be studied over long time scales, using primarily archival data. Our team has access to a number of spectroscopic and photometric facilities. In particular, in order to characterize new transients, LSST data will be complemented with spectra obtained with the new generation of instruments, such as SOXS mounted at the 3.58m ESO-NTT and NTE mounted at the 2.56m NOT. The monitoring campaigns will be complemented by multi-wavelength data, from the X-ray and UV (through Swift observations) to the radio domains.

Site:

INAF - Osservatorio Astronomico di Padova

P.I. & Contact Person:

Andrea Pastorello (INAF - Osservatorio Astronomico di Padova)

Participants:

• E. Mason (INAF - Osservatorio astronomico di Trieste)

• the group studying stellar transients hosted at INAF - Osservatorio Astronomico di Padova

Collaboration with other programs:

• SOXS

• NOT Unbiased Transient Survey 2

LSST Science Collaborations Involved:

• Transients/variable stars

Abstract:

Gravitational waves (GWs) have now been detected from several binary black hole (BH) mergers, binary neutron star (NS) mergers, and, allegedly, from BH-NS mergers as well. In this rapidly evolving multi-messenger field, the frontier is now to be able to characterise the diversity of the EM counterparts to these compact-object mergers. Additionally, new sources of detectable GW emission might be revealed soon, e.g. in the form of a GW-burst from a highly asymmetric stellar explosion or more exotic events.

The role of Rubin-LSST in this topic will be crucial thanks to its ability to rapidly detect these transients whose light curves will constrain the type of event, the composition of the envelope of the source involved and the evolution of the system which give rise to it.

Specifically, the Vera Rubin Observatory ToOs of EM counterparts of GW sources and the serendipitous discoveries from future surveys like the Wide-Field-Deep survey together with specific follow-up observations will uniquely enable the following science: population studies of EM counterparts of NS mergers, very early observations of KNe, discovery of the EM counterparts of NS-BH mergers and discovery of EM counterparts of binary black holes (BH-BH) mergers.

Our team is deeply involved in the EM follow-up of GW sources within the GRAWITA and ENGRAVE and e-PESSTO collaborations having access to instruments, such as VST, TNG, NOT, VLT, XMM-Newton, Chandra, Swift, AGILE, SRT, VLBI. Other collaborations: LIGO/VIRGO and KM3NET.

Site:

INAF - Osservatorio Astronomico di Roma

P.I. & Contact Person:

Silvia Piranomonte (INAF - Osservatorio Astronomico di Roma)

Participants:

• E. Brocato (INAF - Osservatorio Astronomico di Roma)

• M.T. Botticella (INAF - Osservatorio astronomico di Capodimonte)

Collaboration with other programs:

• GRAWITA

• ENGRAVE

• e-PESSTO

• VST

• TNG

• NOT

• VLT

• XMM-Newton

• Chandra

• Swift

• AGILE

• SRT

• VLBI

• LIGO/VIRGO

• KM3NET

LSST Science Collaborations Involved:

• Transients/variable stars

Abstract:

RR Lyrae, Cepheids, MIRA are variable stars, extensively used as primary distance indicators, as they are expected to obey specific period-luminosity relationships. Originally investigated mostly in the Milky Way, the recent developments in the instrumentation facilities allowed detection of these stars also in other Local Group galaxies. The aim of the proposed research project is to use the LSST capabilities in synergy with results from stellar evolution modeling to study variable stars populations in part of the Local Group galaxies within 350 Kpc from the observer. The computational effort, applied to the interpretation of LSST data, will allow to adopt population synthesis techniques for a better understanding of advanced evolutionary phases and to derive information on the past star formation history of the host galaxies.

Site:

INAF - Osservatorio Astronomico di Roma

P.I. & Contact Person:

Paolo Ventura (INAF - Osservatorio astronomico di Roma)

Participants:

• F. Dell'Agli, M. Castellani, F. D'Antona (INAF - Osservatorio astronomico di Roma)

• V. Caloi (INAF - Istituto di Astrofisica e Planetologia Spaziali di Roma)

• M. Groenewegen (Observatory of Bruxelles)

• I. McDonald (University of Manchester)

• M. Salaris (John Moore University Liverpool)

• D. Kamath (Maquarie University, Sidney)

LSST Science Collaborations Involved:

• Transients/variable stars

Abstract:

Our group at the INAF-Osservatorio Astrofisico di Torino (Italy) has been working on active galactic nuclei (AGN) variability since 1994, from both an observational and theoretical point of view. We are especially interested in blazars, the most active AGN. The group includes the leadership of the Whole Earth Blazar Telescope (WEBT), an international collaboration born in 1997 and counting many tens of astronomers. The analysis of the optical, near-infrared, and radio data from WEBT campaigns, often including polarimetry and sometimes spectroscopy besides photometry, and usually complemented by high-energy observations by satellites and ground-based TeV facilities, has led to more than 120 refereed papers. Many more unpublished data are available, which are still to be explored. We have investigated both extrinsic (geometrical) and intrinsic (energetic) variability mechanisms in the AGN jets on different time scales. In particular, we exploited the minute-cadence light curves provided by the TESS satellite to reveal the fastest jet variations. Our group is responsible for selecting and analysing variable AGN as part of the Gaia Data Processing and Analysis Consortium (DPAC).

We are now working for the Gaia Data Release 3 in 2022, when the AGN light curves will be published. We aim at applying our expertise on AGN variability to the analysis of the Rubin-LSST data. We have joined the TVS Science Collaboration (SC) in 2017 and the AGN SC in 2020, and worked actively within them. In particular, we have submitted a white paper for cadence optimization in 2018 and a cadence note in 2021.

Site:

INAF - Osservatorio Astrofisico di Torino

P.I. & Contact Person:

Claudia M. Raiteri (INAF - Osservatorio Astrofisico di Torino)

Participants:

• M. Villata, M. Carnerero (INAF - Osservatorio Astrofisico di Torino)

Collaboration with other programs:

• Whole Earth Blazar Telescope (WEBT; https://www.oato.inaf.it/blazars/webt/)

• MAGIC, Fermi, AGILE teams

• Gaia Data Processing and Analysis Consortium (DPAC)

• Key-Project on Blazar Monitoring ongoing at the Italian Radio Telescopes

LSST Science Collaborations Involved:

• Transients/variable stars

• AGN

Abstract:

The search for transient phenomena in the Universe has entered a new era with the advent of synoptic surveys discovering new classes of transients with no galaxy bias, probing shorter timescales and fainter magnitudes and exploring the physical diversity in the transient zoo that will challenge the paradigms we hold for stellar deaths. The main aim of our research programme is to constrain the progenitor stars of different types of transients through the analysis of their occurrence rates in stellar populations with different ages and chemical compositions.

The LSST survey will provide a large number of transients in galaxies with a large range of ages, strongly reducing both the statistical and the systematic uncertainty. We plan to seize this upcoming opportunity to shed light on transient progenitor stars. Our research interests cover a large range of topics of both transient studies (from detection to classification) and galaxy studies (from source extraction to SED analysis and SFH modelling), has a twofold nature (observational and theoretical) comparing predictions from different progenitor models with specific observations, aims to explore innovative approaches for photometric classification of transients and benefits from synergies between programs as such as SOXS, Euclid and SKA. Our team includes experts in the analysis of multi-wavelength transient search, in transient classification, in the modelling of progenitor stars and has leading roles in international programmes to study the transient Universe. We also work closely with the programme for INAF involvement in Rubin-LSST as well as with the wide international Rubin Community.

Site:

INAF - Osservatorio Astronomico di Capodimonte

P.I. & Contact Person:

Maria Teresa Botticella (INAF - Osservatorio astronomico di Capodimonte)

Participants:

• F. Ragosta, M. T. Botticella, M. Paolillo, V. Petrecca (INAF - Osservatorio Astronomico di Capodimonte)

• E. Cappellaro, L. Greggio, S. Benetti, A. Pastorello, N.E. Rosa, L. Tartaglia (INAF - Osservatorio astronomico di Padova)

• S. Piranomonte, E. Brocato (INAF - Osservatorio astronomico di Roma)

• S. Campana, P. D'Avanzo, M. Landoni (INAF - Osservatorio astronomico di Brera)

• G. Pignata (Universidad Andres Bello)

• L. Izzo (Dark Cosmology Centre)

• S. Smartt (Queen’s University of Belfast)

• M. Vaccari (University of the Western Cape South Africa)

• F. Bianco (University of Delaware)

• W. Clarkson (University of Michigan-Dearborn)

Collaboration with other programs:

• SOX

• Euclid

• ENGRAVE

• ThunderKAT

• SKA

Access to further facilities:

• VST

• MeerKAT

LSST Science Collaborations Involved:

• Transients/variable stars

• Dark Energy

Abstract:

The early LSST data releases will be a goldmine to characterise stellar populations in our Galaxy and its satellites: a perfect laboratory for galaxy formation and evolution. Observed properties of variable stars (RR Lyrae, PopII/Anomalous/Classical Cepheids, Miras) and our set of theoretical models we can support projects concerning:

a) The 3D-structure of The Milky Way and dwarf galaxies -- Combining Gaia and Rubin-LSST data we will construct a broad spatial view of the Halo and dwarf galaxies, and in particular, their stellar streams and tidal tails. Variable stars are excellent distance indicators and we developed new algorithms (REDIME) to simultaneously estimate individual distances, reddening and metallicity of regular variables based on our evolutionary and pulsation framework. We plan to complement LSST data with new single epoch NIR observations (Italian GTO time with ERIS@VLT).

b) Bulge/Halo-Dwarfs connection -- Stellar metallicity contains crucial imprints to trace galaxy formation. We collected the largest and most homogeneous spectroscopic data set for Halo RRLs (~9,000). We used this dataset to develop and calibrate photometric indicators (REDIME, Fourier parameters) to push metallicity estimates well beyond the spectroscopic limit (V~19-20 mag). We plan to extend this approach to Rubin-LSST bands and to explore RRLs in the Halo outskirts, in the bulge and in nearby dwarfs.

Site:

INAF - Osservatorio Astronomico di Roma in collaboration with University of Rome Tor Vergata

P.I. & Contact Person:

Giuliana Fiorentino (INAF - Osservatorio Astronomico di Roma)

Participants:

• M. Di Criscienzo, M. Fabrizio (INAF - Osservatorio Astronomico di Roma)

• G. Bono (University of Rome, Tor Vergata)

• M. Dall'Ora, S. Leccia, M. Marconi, R. Molinaro, I. Musella, V. Ripepi (INAF - Osservatorio Astronomico di Capodimonte)

• P.B. Stetson (DAO, Canada)

• C. Sneden (University of Texas, USA)

• G. Preston (Carnegie Observatories)

• B. Chaboyer (Dartmouth University)

• F. Thevenin (Nice Observatory, France)

• B. Lemasle (University of Heidelberg)

• M. Salaris (Liverpool University, UK)

• E. Valenti, M. Romaniello (ESO)

• M. Marengo (Iowa State University, USA)

• M. Zoccali (PUC University, Chile)

• N. Matsunaga (University of Tokyo, Japan)

Collaboration with other programs:

We will support spectroscopic follow up of Rubin-LSST targets to provide metallicity estimates and dynamical parameters. This can be done using near future spectroscopic surveys (WEAVE, MOONS@VLT, MAVIS@VLT [GTO time, AO assisted]) and with Italian facilities (HARPS-N/GIANO-B at TNG, PEPSI/LINC-NIRVANA at LBT).

LSST Science Collaborations Involved:

• Transients/variable stars

• Stars, Milky Way, and Local Volume

Abstract:

Detection of streams, substructures and faint stellar systems in and beyond the Milky Way (MW) is crucial to shed light onto the origin and early history of our Galaxy and its Local Group companions.

In the past 20 years many new stellar systems were discovered (Willman 2010 and references therein) thanks to large surveys such as SDSS (York et al. 2000), DES (Drlica-Wagner et al. 2015), VVV (Minniti et al. 2017) and Gaia (e.g. Belokurov et al. 2018; Helmi et al. 2018). However, many diffuse, faint systems still lay undetected below the magnitude limits reached by these surveys.

The Rubin Observatory Legacy Survey of Space and Time (LSST) will dramatically increase the amount and depth of current observations, reaching V <= 27.6 mag (Tyson and the LSST Collaboration 2003) over the whole southern hemisphere.

Building on expertise developed in processing pulsating stars observed by Gaia and our early access to data from that mission, we will exploit the outstanding photometric capabilities of LSST in order to search for undiscovered ancient stellar structures using Population II tracers such as the RR Lyrae stars (RRLs).

RRLs are excellent tracers of the oldest stars (ages t>~ 9-10 Gyr) which witnessed the first epoch of galaxy formation. They are also invaluable distance indicators and the only tracers with a small relative distance error (~5%), particularly at large distances, but also at 5 - 10 kpc, they will be the stars with the most precise distances. And this is important for a plethora of applications, from tidal streams, to dynamics, to validation of distances and extinction maps.

The project will combine the following products/deliverables of LSST:

(i) the detection of Population II pulsating variables;

(ii) a photometric database containing multiband photometry and astrometry for billions of sources.

Machine learning / deep learning algorithms (like Artificial Neural Networks) will be applied to RRLs and other Population II tracers detected by the LSST to identify new stellar structures and the "building blocks" that contributed to the build up of galactic halos.

Site:

INAF - Osservatorio di Astrofisica e Scienza dello spazio di Bologna

P.I. & Contact Person:

Gisella Clementini (INAF - Osservatorio di Astrofisica e Scienza dello spazio di Bologna)

Gaia DPAC member, leader of the work page devoted to the specific processing and characterisation of RR Lyrae stars and Cepheids observed by Gaia

Participants:

• A. Garofalo, T. Muraveva (INAF - Osservatorio di Astrofisica e Scienza dello spazio di Bologna, DPAC members, Coordination Units 7 - Variability, and 9 - Catalogue validation)

• Researchers at INAF - Osservatorio astronomico di Capodimonte and INAF - Osservatorio astrofisico di Torino

• Members of Gaia DPAC in Switzerland (CU7 team), France (CU6 team)), Nederland (Helmi and Balbinot, CU9 team), Spain (Sarro, Delgado, CU8 team)

LSST Science Collaborations Involved:

• Transients/variable stars

• Stars, Milky Way, and Local Volume

Abstract:

We propose the study of star forming regions and young stellar objects, including their variability at all the time scales (from hours to years), to probe different processes: accretion bursts (including e.g. Exors), warp disk, extinction, magnetic activity, mapping of angular momentum evolution with stellar age, etc. This investigation is complemented with spectroscopic follow-ups, as the team has a strong expertise and involvement in several facilities as GES, WEAVE, 4MOST, SoXS, JWST. Multi-wavelength characterisation will also be addressed, taking advantage of the involvement of the team in current and future X-ray missions as eROSITA, Chandra, XMM, Athena. An interdisciplinary approach combining multi-band observations with magnetohydrodynamic models, and laboratory experiments are also offered, as already done in the past by the team.

The HPC facility "Sistema di Calcolo per l'Astrofisica Numerica" hosted at the INAF-OAPa will be available for the project. It consists of a HPC cluster based on 4896 cores Intel Xeon Phi7250 at 1.4 GHz, and equipped with the new Intel OmniPath architecture for high-performance interconnectivity.

This work will be coordinated with the expertise achieved in the last years within TVS and SMWLV SCs for the use of the Rubin Science Platform and the Data Preview 0, being the PI also the chair of dedicated Task Forces in TVS. The work done in the White Papers Bonito+ 2018, Prisinzano+ 2018 and in the Cadence Notes Bonito+ 2021 and Prisinzano+ 2021 will be used as starting point for the investigation here proposed (see also Survey Strategy Session led by the PI at PCW 2021).

Site:

INAF - Osservatorio Astronomico di Palermo

P.I. & Contact Person:

Rosaria (Sara) Bonito (INAF - Osservatorio Astronomico di Palermo)

Participants:

• T. Giannini (INAF - Osservatorio astronomico di Roma)

• A. Caratti o Garatti (INAF - Osservatorio astronomico di Capodimonte)

• L. Prisinzano, S. Orlando, M.G. Guarcello (INAF - Osservatorio Astronomico di Palermo)

• K. Stassun (Dept. of Physics and Astronomy, Vanderbilt University, USA)

• E. Feigelson (Departments of Astronomy & Astrophysics and of Statistics, Penn State University, USA)

• P. Hartigan (Physics and Astronomy Dept. Rice University, Texas, USA)

Collaboration with other programs:

• GES

• WEAVE

• 4MOST

• SoXS

• JWST

LSST Science Collaborations Involved:

• Transients/variable stars

• Stars, Milky Way, and Local Volume