Seminars

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13/05/2021 - 12:30
SO Webloquio: The HIRES/ELT consortium, instrument and science
We present the results from the phase A study of ELT-HIRES, an optical-infrared, high-resolution spectrograph for ELT, which has just been completed by a consortium of 30 institutes from 12 countries forming a team of about 200 scientists and engineers. The top science cases of ELT-HIRES will be the detection of life signatures from exoplanet atmospheres, tests on the stability of Nature's fundamental couplings, the direct detection of the...
Dr. Alessandro Marconi
11/05/2021 - 12:30
Is the Bremer Deep Field Ionised at z=7?
The talk will show that the population of star forming galaxies in the Bremer Deep Field (BDF) has formed two large ionised bubbles. The sources in the BDF have been completed with a set of expected, though not detected, low luminosity sources at z ~ 7. We have estimated the number of ionising photons produced per second by the different star forming galaxies in the BDF and have compared it with the number that would be required to reionise...
Jose Miguel Rodriguez Espinosa
06/05/2021 - 12:30
SO Webloquio: Nuclear star clusters
I review the current knowledge about nuclear star clusters (NSCs), and the spectacularly dense and massive assemblies of stars found at the centers of most galaxies. Understanding the formation, growth, and ultimate fate of NSCs is crucial for a complete picture of galaxy evolution. There is a clear transition mass in galaxies of ∼ 10^9 Msol where the characteristics of NSCs change. I argue that at lower masses, NSCs are formed primarily from...
Dr. Nadine Neumayer
04/05/2021 - 12:30
SO Web-Colloquia: Thematic area 9 of the CSIC’s new White Book: Understanding the basic components of the Universe, its structure and evolution
CSIC is about to publish a White Book to define its scientific strategy for the coming decades. The White Book contains chapters on 14 different thematic areas. One of the main goals of this exercise is to increase collaboration between research groups and institutes of the CSIC. Particular value is set on inter- and cross-disciplinary work. Each thematic area defines a set of “challenges”, key scientific questions for the coming decade(s) in...
Dr. María José Costa and Dr. Rainer Schödel
29/04/2021 - 12:30
Extreme Blazars
Blazars are jetted active Galactic Nuclei with the jet axis oriented close to the line of sight of the observer. Non-thermal emission processes in the jet cover the whole electromagnetic spectrum from radio wavelengths to TeV gamma rays, with a characteristic double-humped Spectral Energy Distribution (SED). Relativistic amplification effects on the observed fluxes make their jets ideal candidates for detection at any wavelength. A physically...
Dr. Giacomo Bonnoli
27/04/2021 - 12:30
SO Webloquio: Chaos and Instabilities in Planetary Systems
The aim of this talk is to discuss recent results on the estimation of instability times through Shannon entropy and its application to planetary systems. We will analyze the complex relation between chaos and orbital instability, and how each is able to provide important information about the dynamical evolution of the system. Finally, we will analyze how different well known planetary systems These concepts will then be applied to several...
Dr Cristian Beauge
22/04/2021 - 12:30
Gas-poor clusters: what kind of beasts are they?
The known variety of galaxy clusters is constantly increasing with our progress in understanding the severity of selection effects on observational samples and with obvious implications on cosmology and cluster physics. In the talk, after a general introduction on galaxy clusters and a reminder on selection effects, I present perhaps the first X-ray unbiased sample of clusters with known masses and X-ray follow-up, its more variegate nature...
Dr. Stefano Andreon
15/04/2021 - 12:30
Unveiling the low surface brightness Universe
From the beginning of time, humankind has wondered what lies behind the darkness of the night sky. From the pre-telescope era to the present, our ability to see the lowest surface brightness details in the sky has improved by a factor of one million. In this talk, I describe how our vision of the sky has changed over time and how the recent developments in ultra deep imaging have speed up our capacity to discover new objects and structures in...
Dr. Ignacio Trujillo
08/04/2021 - 12:30
On the effects of Initial Mass function on the galactic chemical enrichment: the role of Pair Instability Supernovae
We built new sets of chemical yields from massive and very massive stars up to Mi ~ 350 Msun, by combining the wind ejecta extracted from our hydrostatic stellar evolution models with explosion ejecta from the literature. Using a simple chemical evolution code we analyse the effects of adopting different yield tables by comparing predictions against observations of stars in the solar vicinity. Our study indicates that PISN played a significant...
Dr. Sabyasachi Goswami
06/04/2021 - 13:30
SO Webloquio: James Webb Space Telescope Capabilities for Planet and Exoplanet Observations
JWST, scheduled for launch in October, will bring a new generation of instruments, infrared detectors, and a passively cooled 6.5 m primary mirror to space-based astronomy. I will discuss its imaging and spectroscopic modes, which cover wavelengths from 0.6 - 28.5 microns, and the observatory's moving-target tracking, and coronagraphic and time-series modes for direct or transit observations of exoplanets. I will show some statistics for the...
Dr. John Stansberry
30/03/2021 - 12:30
SO Webloquio: Star-forming Complexes in Local Mergers and High Redshift Galaxies
Disk galaxies at high redshift contain star-forming complexes, or clumps, whose masses and sizes far exceed those of clumps in local non-interacting galaxies. However, our recent Hubble Space Telescope observations reveal that local merging galaxies can form massive clumps like those at high z, with the same range of physical size, surface density, age, and star formation rate. These similarities, combined with the loss at high redshift of low...
Dr. Debra Elmegreen
25/03/2021 - 12:30
SO Webloquio: Searching for the formation mechanisms of brown dwarfs
New generation of Submillimeter facilities in the North of Chile, like the APEX antenna and the Atacama Large Millimeter/submillimeter Array (ALMA), offers for the first time the possibility for studying the formation of stars, brown dwarfs, and planets with unprecedented sensitivity and angular resolution in the millimeter/submillimeter regime. The formation of Brown Dwarfs (BDs) is a debated topic of research. The most widely discussed...
Dr. Itziar de Gregorio Monsalvo
18/03/2021 - 12:30
SO Webloquio: Polarimetry in the planetary sciences
The past few decades have been characterized by the rapid development of astronomical polarimetry that has resulted from new polarimetric instrumentation, new techniques and new theories. Such advances have aided the exploitation of polarimetry in areas ranging from solar system bodies to exoplanets and allowed the development of completely new fields of polarimetric exploration such as cometary nuclei, transneptunian objects, protoplanetary and...
Dr. Ricardo Gil-Hutton
11/03/2021 - 12:30
Optical polarization of radio-quiet active galactic nuclei and its repercussion within the changing-look scenario
The core of Active Galactic Nuclei (AGN) remains under the resolution limit of the vast majority of current telescopes. However, polarimetry provide us with information of those unresolved regions, which would be inaccessible in natural light, such as the presence of dust, magnetic fields or scattering regions. This talk will be focused on the optical polarization properties of radio-quiet AGN and its relation with the geometry of the scattering...
Dr. Beatriz Agis González
04/03/2021 - 12:30
SO Webloquio: Multiple stellar populations in globular clusters: Properties, origin, open questions
Globular clusters (GCs) are fascinating objects nearly as old as the Universe that provide insight on a large variety of astrophysical and cosmological processes. However, their formation and their early dynamical evolution are far from being understood. In particular, the classical paradigm describing GCs as large systems of coeval stars formed out of chemically homogeneous material has been definitively swept away by recent high-precision...
Dr. Corinne Charbonnel
25/02/2021 - 12:30
SO Web-Colloquia: The exoplanet revolution
The wealth and diversity of planetary systems that have now been detected modified our perspective on planet formation as a whole and more specifically our place in the Univers. It also present an opportunity of historical perspectives and an irresistible call to look for signs of life on these new worlds as a way to explore our own origins. I will introduce the audience with the challenges and recent progresses in this new field of research and...
Dr Didier Queloz
18/02/2021 - 12:30
SO Web-Colloquia: The Search for Advanced Extraterrestrial Civilisations via Anomalies in Astronomical Survey Data
Energy-intensive civilisations are likely to have a significant impact on both their local and extended environments – we already see evidence for this here on Earth. Advanced technical civilisations may reveal themselves to other civilisations by introducing anomalous signals into astronomical data. Artificial radio signals are perhaps the best known example but there are also many other possibilities e.g. excess infra-red emission due to waste...
Dr. Mike Garrett
11/02/2021 - 12:30
SO Web-Colloquia: The influence of the star-forming environment on planetary systems
Planet formation occurs at the same time as star formation, and so the environments in which stars are born are also the birthplaces of planetary systems. Star forming regions are very dense, meaning that encounters between stars and planetary systems are common. Furthermore, the intense UV radiations fields from intermediate and massive stars can truncate, or destroy protoplanetary discs. In this talk, I will describe the detrimental effects of...
Dr. Richard Parker
04/02/2021 - 12:30
PHANGS-Halpha : A narrow-band survey of nearby star-forming galaxies observed with ALMA
This work collects a representative sample of star-forming galaxies as part of a major effort the Physics at High Angular resolution in Nearby GalaxieS (PHANGS) collaboration has been making to build surveys with matched cloud-scale resolutions. Observations resolved at 50–150 pc are necessary to isolate individual Giant Molecular Clouds (GMCs) and HII regions to probe different phases of star formation from cold gas to stellar clusters. In this...
Dr. Alessandro Razza
28/01/2021 - 18:00
SO Web-Colloquia: Vera C. Rubin Observatory: A Big Data Machine for the 21st Century
Vera C. Rubin Observatory and its Legacy Survey of Space and Time (LSST) boasts an 8.4-m diameter mirror, a camera the size of a bus, and a 3.2-gigapixel detector. It will image the entire southern sky from Chile every few nights beginning in 2023, and enable astrophysics on all scales, from near-Earth asteroids to cosmic acceleration. With nightly data volumes around 20 TB and a final data release of 15 PB, LSST is ushering in a new paradigm...
Dr. Meredith Rawls
21/01/2021 - 12:30
SO Web-Colloquia: Osiris-Rex: results on a mission to understand planetary systems
In September 2016, the NASA OSIRIS-REx spacecraft was successfully launched from Cape Canaveral Air Force Station, in Florida. That was the beginning of an amazing journey to reach near-Earth asteroid Bennu, collect a sample of material from its surface, and bring it back to Earth in 2023. The so-called “Touch-And-Go” maneuver or TAG, took place on October 20, 2020 and the sample collector head has been safely placed into the Sample Return...
Dra. Julia de León
14/01/2021 - 18:00
SO Web-Colloquia: The Blanco DECam Bulge Survey
The Blanco Dark Energy Camera (DECam) Bulge survey is a Vera Rubin Observatory (LSST) pathfinder imaging survey, spanning ∼ 200 sq. deg. of the Southern Galactic bulge, −2◦
Dr. Michael Rich
12/01/2021 - 12:30
SO Web-Colloquia: Primordial black holes, gravitational waves and dark matter
More than twenty years ago, we predicted that massive primordial black holes (PBH) would form via the gravitational collapse of radiation and matter associated with high peaks in the spectrum of curvature fluctuations, and that they could constitute all of the dark matter (DM) today. In 2015, we predicted the clustering and broad mass distribution of PBH, which peaks at several Msun, and whose high-mass tails could be responsible for the seeds...
Dr. Juan García-Bellido
18/12/2020 - 12:30
SO Webloquia: ESO: supporting European leadership in ground-based astronomy
ESO is de facto the lead world-wide organisation in building and operating most powerful ground-based astronomical observatories. The success of the organisation relies on the support of its member states and the cooperation with the community, among other key factors. Over 1000 refereed papers are published every year using data from ESO facilities, with an increasingly larger fraction of these data coming from the archive. Among these...
Prof. Xavier Barcons
17/12/2020 - 12:30
SO Web-Colloquia: On the formation of stellar clusters
In this presentation, I will show how the analysis of the spatial distribution of young stars (YSO) and its comparison to the core population can reveal stellar formation episodes in star forming regions, and help us understand the fragmentation process. I will focus in particular on two very different regions: the relatively massive cluster NGC2264 and the Taurus association. Our recent study of the clump and YSO populations in NGC 2264...
Dra. Estelle Moraux
10/12/2020 - 12:30
SO Web-Colloquia: Stellar population gradients and kinematics of ETGs as revealed by MaNGA
In this talk I will summarise the findings presented in a series of four papers dedicated to the study of early type galaxies (ETGs) with integral field spectroscopy (IFU) from the MaNGA survey. The formation channels and mass assembly of ETGs is still a matter of debate in current galaxy evolution models. The combined analysis of galaxy kinematics and stellar population gradients (age, metallicity, alpha-enhancement, initial mass function -IMF...
Dra. Helena Domínguez Sánchez
03/12/2020 - 12:30
From direct imaging to gravitational waves: tracing the life of gas giant exoplanets
In two decades, the field of exoplanet science has undergone nothing short of a revolution. With such a variety of planetary systems detected, the next step in exoplanet research is to characterise the properties of these systems. In this talk I will focus on “life and adventures” of gas giant exoplanets, and present how future space missions such as JWST, ARIEL and LISA will help us understand the nature, formation and evolutionary history of...
Dr. Camilla Danielski
19/11/2020 - 12:30
SO Web-Colloquia: Flaring on the Sun at all scales
The Sun shows activity across a wide range of size and energy scales. We shall take a journey from the smallest scale events to the largest energy releases in the solar system. The energy release is due to the magnetic fields on the Sun and how they interact. Using EUV/UV spectroscopy different layers of the solar atmosphere can be probed in order to understand the physical processes that occur. The EUV imaging spectrometer onboard the Hinode...
Dr. Louise Harra
12/11/2020 - 12:30
SO web.Colloquio: GRAVITY+, all Sky, High Contrast, Milli-Arcsecond Optical Interferometric Imaging and Spectroscopy
GRAVITY and the VLTI have transformed high angular resolution astronomy with groundbreaking results on the Galactic Center, active galactic nuclei, and exoplanets. The GRAVITY+ project will soon boost optical interferometry to the next level, opening up the extragalactic sky for milli-arcsecond resolution interferometric imaging, giving access to targets as faint as K = 22 mag, and providing ever higher contrast for the observation of...
Dr. Frank Eisenhauer
05/11/2020 - 12:30
SO Web-Coloquia: The Arecibo Observatory Roadmap for the Future: science enhancement plans under UCF management
The Arecibo Observatory (AO) has supported cutting-edge research in the fields of Astronomy, Planetary Science, and Space Atmospheric Science for decades. The unprecedented sensitivity of the Arecibo antenna has led to fundamental contributions in a wide variety of research programs, including the first detection of an exoplanet around pulsar (Wolszczan...
Dr. Noemi Pinilla-Alonso
29/10/2020 - 17:00
Our Galactic Center: A Unique Laboratory for the Physics & Astrophysics of Black Holes
The proximity of our Galaxy's center presents a unique opportunity to study a galactic nucleus with orders of magnitude higher spatial resolution than can be brought to bear on any other galaxy. After more than a decade of diffraction-limited imaging on large ground-based telescopes, the case for a supermassive black hole at the Galactic center has gone from a possibility to a certainty, thanks to measurements of individual stellar orbits. The...
Dr. Andrea Ghez
22/10/2020 - 12:30
We’ve never imaged the Sun’s surface from that close. Solar Orbiter will change that
In February 10, 2020, Solar Orbiter, the new ESA's Sun-exploring mission built in collaboration with NASA, was successfully launched atop an ULA Atlas 5 rocket from Cape Canaveral in Florida. Equipped with ten instruments, six for remote sensing and four for in-situ measurements of the solar heliospheric conditions, it will get as close as 0.28 astronomical units (or 42 million kilometres) to the Sun in a mission that can last more than ten...
Dr. David Orozco
15/10/2020 - 12:30
So Web-Colloquia: The star formation process on cloud-scales in nearby galaxies
Where do stars form and how is their formation regulated across galactic disks are two critical questions for our understanding of the star formation process. High angular observations of nearby galaxies allow us to sample the star formation process across entire galactic disks reaching now regularly the scales of the star-forming units, namely Giant Molecular Clouds (GMCs) and HII regions. Such data provide new insights on the molecular gas...
Dr Eva Schinnerer
08/10/2020 - 12:30
SO Web-Colloquia: Recent findings on nova explosions
Nova events are the result of the interaction of low-mass binary systems. A compact white dwarf (WD) accretes material from an old and cold companion until a thermonuclear runaway takes place on its surface. Such explosive events can be considered the scaled-down siblings of supernova (SN) explosions, but its study has many advantages over SNe, as nova events are more numerous (some systems even exhibit recurrent explosions within decades) and...
Dr. Toalá Sanz
01/10/2020 - 12:30
SO Web-Colloquia: Following black hole evolution from z=5: mergers and outflows
The growth and evolution of the most massive black holes, and their host galaxies, can be followed from z=7 and even earlier. The critical events that shape this evolution are major mergers, Eddington or super-Eddington accretion, violent star formation, and powerful outflows. I will present the results of a systematic study of 40 AGN at z~4.8 using Gemini, VLT, Herschel and ALMA. Our recent (2019) ALMA data allow a fresh look at major mergers...
Dr. Hagai Netzer
24/09/2020 - 12:30
The power of low activity black holes
It is possible that most galaxies host a black hole at the centre, most of the time this being in a relatively quiescent state. The so-called low luminosity Active Galactic Nuclei are characteristic of this phase. These objects represent the vast majority of the active galactic nuclei (AGN) population in the near universe, and still the least conforming class with the standard AGN scenario. Their low luminosity is at odds with their often...
Dr. Almudena Prieto
17/09/2020 - 12:30
SO Web-Colloquia: J-PAS: First light results of the JPCam
The Javalambre-Physics of the Acclerating Universe Asptrohysical Survey (J-PAS) have just started to scan thousands of square degrees of the northern sky with 56 narrow band filters and the JPCam instrument with the telescope 2.5m of the Javalambre Observatory. Before the JPCam started its operation, we have observed with the pathfinder camera one sq. deg on the AEGIS field (along the extended Groth Strip). This colloquium will present the...
Dr. Silvia Bonoli
10/09/2020 - 12:30
SO Web-loquio: Massive black hole binaries in the cosmos
Massive black holes weighing from a few thousands to tens of billions of solar masses inhabit the centers of today's galaxies, including our own Milky Way. Massive black holes also shone as quasars in the past, with the earliest detected a mere one billion years after the Big Bang. Along cosmic time, encounters between galaxies hosting massive black holes in their centers have produced binary massive black holes that eventually coalesced by...
Dr. Marta Volonteri
03/09/2020 - 12:30
SO Web-loquio: Active Galactic Nuclei: fueling and feedback
Dynamical mechanisms are essential to exchange angular momentum in galaxies, drive the gas to the center, and fuel the central super-massive black holes. While at 100pc scale, the gas is sometimes stalled in nuclear rings, recent observations reaching 10pc scale, or 60mas with ALMA, have revealed, within the sphere of influence of the black hole, smoking gun evidence of fueling. Observations of AGN feedback will be described, together with the...
Dr. Françoise Combes
30/07/2020 - 12:30
SO Webloquio:The Orion Radio All-Stars: new insights into YSO radio emission, using the VLA, VLBA, and ALMA
With significant new observing capabilities, centimeter-wavelength radio astronomy is currently in a renaissance leading up to the advent of the Square Kilometre Array (SKA), highlighting new opportunities and also technical challenges. The sensitivity upgrades of both the NRAO Very Large Array (VLA) and the Very Long Baseline Array (VLBA) have begun to provide us with a much improved perspective on stellar centimeter radio emission,...
Jan Forbrich
23/07/2020 - 12:30
X-ray Astronomy for non (X-ray) astronomers
Observations of X-rays coming from outside the solar system were pioneered in 1962 by Riccardo Giacconi and colleagues. From that very day, it became evident that X-rays would reveal a very different Universe to that shown by optical or radio telescopes. Indeed, X-rays are typically produced in the environment of black holes, or where the ambient temperature exceeds millions of degrees. X-ray telescopes (which, for good reason, are in orbit)...
Dr. Xavier Barcons
25/06/2020 - 12:30
Peering into the Dark: Probing the Formation and Early Evolution of Massive Stars
This presentation will focus on recent work aimed at understanding the formation and early evolution of massive protostars. The massive (M>8 Msol) stars into which these evolve are the primary drivers of galactic ecosystems. The energy and nuclear processed material these massive stars inject into their enviroment during their lives and ultimately as supernovae, shapes the physical and chemical evolution of the ISM in galaxies. These stars...
Dr. Gary Fuller
18/06/2020 - 12:30
Exploring the origin of gas-rich ultra-diffuse galaxies with HI kinematics
Ultra-diffuse galaxies (UDGs) are one of the most discussed topics in extra-Galactic astronomy in the last lustrum given their puzzling properties: they have luminosities typical of dwarf galaxies, but optical scale lengths similar to very massive spirals. This intriguing combination is hard to explain, and up to date the precise formation mechanism of UDGs remains unknown. With the goal of learning more about their origins, our group has...
Pavel E. Mancera Piña
04/06/2020 - 12:30
TuMaG: un magnetógrafo para Sunrise III
After the scientific success of the two first flights of the Sunrise stratospheric balloon mission, the international consortium led by MPS (Göttingen, Germany) decided to re-issue the mission for a third time. For Sunrise III, a new gondola and navigation system will be provided by APL (Johns Hopkins University, MD) and the re-furbished telescope by MPS. The latter also provides the instrumental platform and the light distribution system while...
Dr. José Carlos del Toro Iniesta
28/05/2020 - 12:30
Galaxy clusters and their environment
Clusters of galaxies are located at the intersection of cosmic filaments. I will first describe how we have found large extensions around clusters, at optical and/or X-ray wavelengths, suggesting that we are indeed detecting the cosmic web around clusters, and I will discuss some galaxy properties in one of these extended filaments. At the cluster scale, I will then describe our searches for substructures in X-rays and show how X-ray...
Dr. Florence Durret
14/05/2020 - 12:30
Gamma-ray Emitting Narrow Line Seyfert 1 Galaxies: Past, Present, & Future
The detection of significant gamma-ray emission from about a-dozen radio-loud narrow line Seyfert 1 (NLSy1) galaxies by Fermi-Large Area Telescope has opened up a realm to explore the physical conditions needed to launch relativistic jets in a different central engine and host galaxy environment than that is known for more-common jetted active galactic nuclei, i.e. blazars. Promising results acquired from various multi-wavelength campaigns are...
Dr. Vaidehi S. Paliya
31/03/2020 - 12:30
HI mapping of nearby dwarf galaxies with SKA pathfinders: unique capabilities of KAT-7 and MeerKAT
Dwarf galaxies are by far the most numerous galaxies in the Local Universe. Their simple structure and proximity provides a unique window to the detailed investigation of various processes necessary for galaxy formation and evolution. One of the most reliable approach for studying the evolution of galaxies is to look at their physical properties using the neutral hydrogen gas (HI).  In this talk I will present ongoing work on the HI properties...
Dr. Brenda Namumba
19/03/2020 - 12:30
Study on astrophysical masers in the era of SKA/SKA-VLBI
In my colloquium talk, out of the introduction topics mentioned above, I will focus my talk on trigonometry of maser sources yielded with the Square Kilometre Array (SKA) Phase 1. This is one of the science cases that have been planned as Japanese scientific contributions to SKA1. Its key issue is the scientific and technical feasibility in the low frequency band, corresponding to SKA1-MID Band 2 around 1.6 GHz, in which atmospheric effects on...
Dr. Prof Hiroshi Imai
17/03/2020 - 12:30
Magnetic fields, rotation, and activity in M dwarf stars
M dwarfs are known to generate the strongest magnetic fields among main-sequence stars with convective envelopes, but we are still lacking a consistent picture of the link between the magnetic fields and underlying dynamo mechanisms, rotation, and activity. For instance, models predict that the maximum magnetic flux a star can generate scales with convective energy stored in its envelope, but no accurate measurements existed until recently....
Dr. Denis Shulyak
05/03/2020 - 12:30
Round Table: Dia de la Mujer
To be provided
Round Table

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