Scientific seminars exposed by scientists and technologists of the IAA and the many centers and research institutions who visit us. They show the intense scientific exchange, they are held at 12:30 every Thursday. Seminars are broadcasted live at IAA - CSIC Seminars Live.



For further information, please contact duffard (at)

Displaying 1 - 50 of 1149


31/12/2023 - 12:30
SO Colloquio: Present and future large radio surveys of the extreme universe
Transient radio emission is a fundamental tracer and physical probe of the most extreme and transient events in the universe. In this talk I will discuss a number of recent developments with existing radio telescopes, including i. the ThunderKAT image-plane transients programme on MeerKAT, ii. The first citizen-science project to search for commensal radio transients, iii. First radio detections of 'VHE GRBs' detected by ground-based Cherenkov...
Dr. Rob Fender
22/06/2023 - 12:30
The First Detections of X-ray Polarization from Supermassive Black Hole Jets and their Physical Implications
X-ray polarization is a crucial probe of the magnetic field structure and emission processes in astrophysical systems. This is particularly true for blazars, active galactic nuclei with powerful jets aligned towards our line of sight. In blazars, X-ray polarimetry allows us to investigate the freshly accelerated particles at the heart of the accelerator. Until now, polarization observations have been limited to the radio-to-optical range,...
Dr. Yannis Liodakis
25/05/2023 - 12:30
TBP: Workshop Gerardo García
18/05/2023 - 12:30
Radio continuum halos in nearby galaxies and the CHANG-ES project
About a decade ago, the upgrade from the classic Very Large Array into the EVLA, i.e. the Karl G. Jansky Very Large Array (VLA), made it possible to observe fainter radio continuum emission than ever before. The project Continuum Halos in Nearby Galaxies - an EVLA Survey (CHANG-ES, PI: J. Irwin) has allowed us to probe gaseous halos of 35 edge-on galaxies with arcsecond details and faint microJansky/beam sensitivities, and to begin answering...
Theresa Wiegert
27/04/2023 - 12:30
Dr. Rubén López Coto
13/04/2023 - 12:30
Coloquio SO: A holistic approach to exoplanet spectroscopy
During the last two decades, multiple observation techniques have enabled the study of exoplanet atmospheres, informing us about their chemical composition, thermal distribution and transport processes. The most successful techniques include low-resolution transit and eclipse spectroscopy, phase curves, and high-resolution Doppler spectroscopy. In all cases, the extraction of the atmospheric signal presents a challenge, being comparable to or...
Guiseppe Morello
30/03/2023 - 12:30
Preparation and Asteroseismic exploitation of the PLATO Mission
Thanks to ultra-precise space missions, we are living an era of big scientific discoveries in the stellar and planetary physics fields. PLATO will capitalise on the developments of successful past missions such as CoRoT, Kepler/K2, TESS and CHEOPS that studied stars and their planetary systems. PLATO will detect and characterise terrestrial exoplanets at orbits up to the habitable zone of solar-type stars. Transit measurements and...
Dr. Javier Pascual
23/03/2023 - 12:30
SO coloquio: Investigating the impact of quasar feedback on the central kiloparsecs of galaxies
Active galactic nuclei (AGN) feedback is the effect that nuclear activity produces in the interstellar and circumgalactic medium of galaxies. Different modes of AGN feedback, which can be broadly divided into radiative/quasar and kinetic/radio, are now considered key processes in the evolution of massive galaxies by regulating black hole and galaxy growth. Indeed, a wealth of observational evidence demonstrates that feedback from supermassive...
Dr. Cristina Ramos Almeida
16/03/2023 - 12:30
An observational study of massive star forming regions at radio wavelengths
In their early stages, massive stars have a profound impact on their hosting cloud as reflected by signposts like shocks, bars and shells of swept material resulting from prominent stellar winds, or photo-ionized (HII) regions produced by energetic irradiance. This activity must be taken into account in the study of the mechanism of formation of either massive stars or nearby lower mass companions affected by such harsh conditions. It is known...
Josep Maria Masque
09/03/2023 - 12:30
When accretion is as vital as extreme: from massive young stars to binary black holes
Accretion is vital for understanding the properties of a number of astrophysical objects, including massive young stars and black holes. For the former, accretion drives the stellar mass growth and multiplicity through gas fragmentation. It also powers strong outflows that regulate the interstellar medium. For black holes, only accretion allows for electromagnetic detection. Hence, the multi-messenger astronomy, for which the loudest sources of...
Dr. Raphael Mignon-Risse
07/03/2023 - 12:30
Sub-milliarcsecond astronomy with Imaging Atmospheric Cherenkov Telescopes
The angular size of a star is a critical factor in determining its basic properties. Together with the distance, it provides the physical diameter of the star which can be used to yield luminosity and mass estimates. Direct measurement of stellar angular diameters is difficult: at interstellar distances stars are generally too small to resolve by any individual imaging telescope. This fundamental limitation can be overcome by several methods...
Dr. Tarek Hassan
02/03/2023 - 12:30
J-PAS: a survey for tracing the role that star formation and environment play in galaxy evolution
The processes that explain the evolution of galaxies from the blue cloud to the red sequence are still under discussion. Internal processes, named as mass-quenching, because they are linked to the galaxy mass or AGN feedback, could be responsible of the rapid quench of the star formation in galaxies. Besides the stellar mass, the evolution of the galaxy populations is also a function of the environment. Unlike the mass quenching, the...
Dr. Rosa González Delgado
23/02/2023 - 12:30
ALMA: Planned Sensitivity Upgrades, and Molecular Gas Imaging of a z=0.376 HI-Detected Galaxy
This talk will cover two distinct topics in progress, one programmatic and the other science: I will first discuss the ALMA Wideband Sensitivity Upgrade (WSU), and then I'll talk about ALMA followup of the highest redshift HI detection in the COSMOS HI Large Extragalactic Survey (CHILES) made with the first 178 hours of observing. With regard to the WSU, the ALMA Project is embarking on a partner-wide initiative to at least double, and...
Dr. Jennifer Donovan Meyer
16/02/2023 - 12:00
School visit
School visit
Sara Garcia.
30/01/2023 - 12:30
SO Coloquio: Dirty Dancing: piercing the dusty environment of merging supermassive black holes
It is a posit of modern astrophysics that most massive galaxies host a super- massive black hole (millions to billions of times more massive than the Sun). These black holes affect the evolution of galaxies well beyond their gravitational sphere of influence (which does not extend wider than 1/1000th of the typical galaxy linear size). In turn, the evolution of galaxies affects the growth of black holes through, e.g., galaxy merging....
Matteo Guainazzi
12/01/2023 - 12:30
CARMENES-PLUS: a technical upgrade for CARMENES and the impact on its science
CARMENES is a dual (VIS: 550 to 950 nm; NIR: 950 to 1700 nm) high-resolution spectrograph installed at the 3.5 m telescope at the Calar Alto Observatory (CAHA, Almería, Spain). The NIR channel spectrograph uses the radial-velocity method for detecting exoplanets around low-mass stars. Thus, a high thermal stability is required in the NIR cooling system to achieve a high precision in radial velocities. The cooling system was originally conceived...
Roberto Varas González
19/12/2022 - 12:30
Fossil groups of galaxies: seeing the future looking at the past
The nature of fossil groups of galaxies has been debated for over more than 3 decades. This is in part because of the lack of deep multiwavelength data and also due to the low purity of samples selected using solely magnitude gap criteria. The initial results of a sample of bonafide fossil groups using X-ray/optical observations has clarified many of their characteristics, such as high central metal abundances and concentration measurements....
Dr. Renato Dupke
01/12/2022 - 12:30
SO Colloquio: Moving from high to extreme precision in air shower observations: From LOFAR to SKAO
Cosmic rays play an interesting role in understanding the most violent objects in the universe. These charged atomic particles reach energies orders of magnitudes higher than achievable in accelerators on Earth, which points towards an origin of the most extreme objects in the universe, with strong magnetic shocks and mass transfer. However, these sources are not firmly identified. Astrophysical interpretations are currently limited by the...
Dr. Anna Nelles
29/11/2022 - 12:30
TARSIS: the Tetra-Armed IFU at Calar Alto designed for the CATARSIS galaxy cluster exploration
In this talk I will present the design of the Integral Field Unit TARSIS, recently selected to be the next generation multi-object spectrograph for the 3.5m telescope at Calar Alto. In addition, I will describe the scientific goals of CATARSIS, the galaxy cluster exploration that will be carried out in the first years of the operation of TARSIS.
Dr. Jorge Iglesias
24/11/2022 - 12:30
SO webloquio: The Milky Way Nuclear Star Cluster
The Milky Way nuclear star cluster (NSC) is located within the nuclear stellar disc (NSD) in the Galactic centre. The NSC and NSD are distinct structures of the Milky Way, but also connected to the larger Milky Way structures, e.g. via the inflow and outflow of gas, and the infall of star clusters. Our knowledge of the larger Milky Way structures, Galactic disc, bulge and halo, has expanded in recent years through surveys and dedicated missions...
Dr. Anja Feldmeier
17/11/2022 - 12:30
SO colloquio: A conclusive test of the cold dark matter model
The ``Lambda cold dark matter'' (LCDM) cosmological model is one of the great achievements in Physics of the past thirty years. Theoretical predictions formulated in the 1980s turned out to agree remarkably well with measurements, performed decades later, of the galaxy distribution and the temperature structure of the cosmic microwave background radiation. Yet, these successes do not inform us directly about the nature of the dark matter. This...
Dr. Carlos Frenk
15/11/2022 - 12:30
The effect of pre-processing on the stellar population content of early-type dwarf galaxies
According to the CDM model, galaxy clusters grow through the accretion of individual galaxies and galaxy groups. Thus, it is a true challenge to distinguish the possible role of the present-day host halo from that of previous ones, in the transformation of accreted galaxies. Dwarf early-type galaxies (dEs) are often regarded as statistically meaningful testbeds for investigating environmental effects mainly due to their high number density and...
Dr. Bahar Bidaran
10/11/2022 - 12:30
SO Colloquio: The Cherenkov Telescope Array: Status and Prospects
The Cherenkov Telescope Array (CTA) will become the reference observatory for Very High Energy (VHE) Gamma Ray Astronomy during the next decades. CTA promises a jump in sensitivity and energy coverage of one order of magnitude over the current instruments, significantly improved energy and angular resolutions and full sky coverage. Over thousand new sources will foreseeably be identified in this range for the first time. VHE gamma rays are...
Dr. Juan Cortina
08/11/2022 - 12:30
The many “phases” of small bodies
Asteroids, comets, and trans-Neptunian objects are collectively known as small bodies. In a way, they are the debris left by the planetary formation in the Solar system, and as such, they carry a lot of information regarding the processes that shaped it. But, small bodies are by no means stationary objects: not only do they move across the sky, but their brightness also changes due to different mechanisms, from rotational variations due to...
Dr. Álvaro Alvarez-Candal
07/11/2022 - 12:30
The ASTRI Mini-Array and its Science
The ASTRI Collaboration is building at the Teide Astronomical Observatory in Tenerife an array of 9 small Cherenkov telescopes capable of observing with good flux sensitivity, energy and angular resolution the gamma-ray sky above an energy threshold of several hundreds of GeV. The ASTRI telescopes adopt a dual-mirror Schwarzschild-Couder optical design. Entrapped amidst the two mirrors the ASTRI camera, based on silicon photon-multipliers...
Dr. Giacomo Bonnoli
28/10/2022 - 12:30
SO Colloquio: Cosmografía: las aportaciones de al-Ándalus y los reinos ibéricos a la Revolución Científica
Si el Señor Todopoderoso me hubiese consultado, antes de embarcarse en la Creación, le habría recomendado algo más simple. Esta frase, supuestamente formulada por Alfonso X "el Sabio", muestra la complejidad del conocimiento cosmográfico en al-Ándalus y en los reinos cristianos que recibieron su acervo científico. La península Ibérica se convirtió a partir del siglo X en puente esencial para que el saber de la civilización grecorromana,...
Dr David Barrado Navascués
27/10/2022 - 12:30
SO colloquio: A new look at the torus of active galactic nuclei
The classical picture to explain the observations of active galactic nuclei (AGN) required a geometrically and optically thick torus of molecular gas and dust to obscure the central engine from some lines of sight. For more than two decades, the torus was believed to be a compact (pc-scale), isolated, and rotating structure. Our recent work in the Galactic Activity, Torus, and Outflow Survey (GATOS), using ALMA and high-angular resolution mid-...
Dr. Almudena Alonso Herrero
25/10/2022 - 12:30
SO Colloquio: Galactic Center: Radiation from black hole candidates and the dynamics of high velocity stars
We summarize recent research results on the radiation mechanism of the Super Massive Black Hole (SMBH) candidate SgrA* and ask the question if there are Intermediate Mass Black Hole (IMBH) candidates in the central stellar cluster. Furthermore we give an update on the most recent high velocity stars in the central arcsecond - that are closest to SgrA*. Here we concentrate on the high velocity star cluster dynamics and on the 4711+ stars with...
Prof. Andreas Eckart
13/10/2022 - 12:30
New developments at the IAA cosmic dust laboratory
The interpretation of astronomical observations of comets and asteroids and of extrasolar objects such as protoplanetary and debris disks is crucial for understanding the origin and evolution of planetary systems. Collecting electromagnetic radiation scattered or emitted by dust particles present in these objects with powerful telescopes is often our only way to observe and characterized them. In situ observations are available for a handful of...
Dr. Juan Carlos Gómez
06/10/2022 - 12:30
Computational Intelligence in the Big Data Context
Computational Intelligence (CI) commonly refers to a variety of bio-inspired and/or human-like techniques that can be applied in optimisation, learning and modelling problems. Broadly speaking, CI comprises Artificial Neural Networks, Fuzzy Sets and Fuzzy Logic and Evolutionary Computation. In the era of big data, CI in conjunction with data mining techniques are expected to help uncover useful knowledge from big data as they are very well...
Dr. Isaac Triguero
26/09/2022 - 12:30
The EnVision mission to Venus: Discovering why our closest neighbour is so different
EnVision was selected as ESA’s 5th Medium-class mission in the Agency’s Cosmic Vision plan, targeting a launch in the early 2030s. The mission is a partnership between ESA and NASA. The primary goal is to provide a holistic view of Venus, from its inner core up to its upper atmosphere by a single mission, and will be the first mission of its kind. More specifically, EnVision will characterise Venus’ core and mantle structure, in order to study...
Dr. Anne Grete Straume
22/09/2022 - 12:30
SO Web-loquio: Old/new problems with Active Galactic Nuclei and AGN application to cosmology
After several decades of studies the basic nature of nuclear activity of galaxies is well understood. However, unexpected behaviour of AGN was already noted in the past, and with rise of the amount of data we see numerous evidences of phenomena which still require explanation, line Quasi-Periodic Ejection sources, and Changing-Look AGN. Also it is now time to address in more detail the physical nature of the simple AGN components like Broad Line...
Prof. Bozena Czerny
21/09/2022 - 16:30
SO Webloquio: Dwarf Galaxies and the Smallest Supermassive Black Holes
Despite traditional thinking, an appreciable population of (relatively small) supermassive black holes may be lurking in dwarf galaxies. Before the last decade, nearly all known supermassive black holes were in the nuclei of giant galaxies and the existence of such black holes in dwarf galaxies was highly controversial. The field has now been transformed, with a growing community of researchers working on a variety of observational studies...
Dr. Amy Reines
16/09/2022 - 12:30
SO Colloquium: Sex and gender analysis in research and Innovation
This lecture aims to increase researchers’ awareness of the current demands for the inclusion of sex and gender in their research. In fact, several governments and granting agencies, such as the European Commission and the Spanish Agencia Nacional de Investigación (AEI), now require that requests for funding address whether, and in what sense, sex and gender are relevant to the objectives and methodologies of the research proposed. Parallel with...
Dr. Capitolina Díaz
13/09/2022 - 12:30
SO Colloquio: Studies on the origins of our solar system
My goal in this colloquium is to apprehend globally the Solar System by describing a vast sample of small bodies, from Near Earth Asteroids to remote Trans-Neptunian Objects. This goes beyond projects that focused on certain populations only. The core of the talk is theoretical, with emphasis on inner structures and rings. Meanwhile, the stellar occultations by these objects will provide an exploratory route to characterize objects with widely...
Dr. Bruno Sicardy
01/09/2022 - 12:30
SO Webloquio: Stellar Magnetism and Extra-Solar Space Weather
The environment around the Sun and other late-type stars is controlled by magnetic fields. The coronal high-energy radiation (Extreme Ultra-Violet and X-ray photons), the structure and strength of stellar winds, as well as transients such as flares, coronal mass ejections (CMEs), and energetic particle events, are some examples of this magnetic influence. Apart from their direct consequences on the star and its evolution, these phenomena will...
Dr. Julián Alvarado-Gómez
21/07/2022 - 12:30
SO Webloquio: Cold gas constraints via HI Intensity Mapping in the SKA era
Intensity mapping surveys of neutral hydrogen (HI) are a new way to measure the large-scale matter distribution of our universe over a wide range of redshifts, and thus constrain cosmological parameters describing the universal expansion. The next generation of radio telescopes and interferometers - in particular the Square Kilometre Array (SKA) - are being designed and built to include optimising the detection of the HI line at low spatial...
Dr. Laura Wolz
14/07/2022 - 12:30
A journey into the Perseus cluster of galaxies
The central black hole of active galaxies accretes large amounts of matter and powers jets of relativistic particles that can propagate beyond the host galaxy. Radio galaxies are particularly bright at ∼ GHz frequencies, when the accelerated electrons interact with the magnetic field and produce strong synchrotron emission. Such galaxies residing in clusters evolve in a hot, diffuse, X-ray emitting plasma (the intracluster medium, ICM) which is...
Dr. Marie-Lou Gendron-Marsolais
07/07/2022 - 12:30
SO Webloquio: Optical interferometric studies of star and planet formation
A first step towards understanding planetary formation is the characterisation of the structure and evolution of protoplanetary discs. Although the large scale disc is understood in some detail, very little is known about the inner few au. In this region, dust grains sublimate, and accretion and ejection take place, affecting the entire disk structure and evolution. In this talk, I will review how optical interferometric observations can...
Dr. Rebeca García López
23/06/2022 - 12:30
Disks around evolved binaries: do they form second-generation planets?
Most of the planets are formed around young stars. But can they also form around dying stars? The origin of the diversity and complexity of the detected exoplanetary systems stems from how they form in protoplanetary disks. These disks are intensively studied around young stars thanks to the high-angular resolution provided by recent instruments (VLT, ALMA). However, similar disks are also found around evolved stars, namely post-AGB binaries,...
Dr. Jacques Kluska
21/06/2022 - 12:30
SO webloquio: Star-planet plasma interactions and radio emissions
Exoplanets are expected to sustain various plasma interactions with their parent star, depending on the stellar and planetary magnetic field strengths and on the sub- or super-Alfvénic wind speed at the planet’s orbit. Three such interactions lead to electron acceleration and subsequent radio emissions in our solar system: magnetized planets hit by the super-Alfvénic solar wind, and the sub-Alfvénic interactions of the unmagnetized moon Io and...
Dr. Philippe Zarka
14/06/2022 - 12:30
Detailed equilibrium and dynamical tides: impact on circularization and synchronization in open clusters
Binary stars evolve into chemically-peculiar objects and are a major driver of the Galactic enrichment of heavy elements. During their evolution they undergo interactions, including tides, that circularize their orbits and synchronize stellar spins, impacting both individual systems and stellar populations. My recent work introduces an accurate implementation of equilibrium and dynamical tides in the stellar population code binary_c, relying...
Dr. Giovanni Mirouh
09/06/2022 - 16:30
SO Webloquio: Space Weather in an Era of Innovative Science
The newest generation of solar observational data is allowing a pivot toward making connections in the various solar physics domains and facilitating advanced modeling for space weather conditions and impacts. We study important physical couplings in the solar atmospheric layers, as well as connections from the solar corona through the heliosphere. To advance our understanding of how solar activity and variability impact space weather conditions...
Dr. Holly Gilbert
07/06/2022 - 12:30
Revisiting the intermediate- to high-mass star formation
Intermediate and high-mass forming stars have a large impact on the interstellar medium and nearby star forming regions. Historically, the study of the general properties of intermediate- to high-mass pre-main sequence stars has been hampered by the lack of a well-defined, homogeneous sample, and because few and mostly serendipitously discovered sources were known. As a consequence, many open problems involving high-mass star formation suffer...
Dr. Miguel Vioque
02/06/2022 - 12:30
SO Coloquio: The Antikythera Mechanism and the Mechanical Universe
The Antikythera Mechanism. An astronomical calculator and display device found in a first century BCE shipwreck, it is mechanically more sophisticated than anything known from the subsequent millennium. I want to argue that we should be showing admiration rather than amazement, and that the Mechanism fits rather well into its historic context. But this fit has major implications for the development of humanity’s view of the Universe.
Prof. Michael G. Edmunds
31/05/2022 - 12:30
SO Webloquio: Empirical and physical properties of Lyman continuum emitters
Lyman continuum emitters are galaxies showing escaping ionizing radiation, which thus contributes to ionizing the intergalactic medium. They may be the dominant source of cosmic reionization. I will present an overview of the observations and modeling of low-z analogs of the sources of cosmic reionisation recently discovered. HST observations, including UV spectroscopy with COS and rest-UV imaging with the WFC3, combined with ground-based...
Dr. Daniel Schaerer
24/05/2022 - 12:30
Time domain astronomy with future X-ray satellites
Accreting black holes emit in X-rays at the wave-band in which THESEUS will be observing (0.3 keV-20 MeV) due to their extreme physical conditions. The softer energy range is devoted to thermal emission from the accretion disc and the harder is due to the existence of a hard X-ray emitting corona (with undefined geometry so far). The importance of one component versus the other gives rise to the diverse state classification of accreting black...
Dr. Maria D. Caballero-Garcia
23/05/2022 - 12:30
New insight into the magnetism of isolated white dwarfs
Many stars evolve into magnetic white dwarfs, but we do not know when the magnetic field appears at their surface, if and how it evolves during the cooling phase, and, above all, what are the mechanisms that generate the field, and why they act on some but not all degenerate stars. Observations may help to find an answer to these questions, but their interpretation is dramatically affected by biases due to target selection and a non-homogeneous...
Dr. Stefano Bagnulo
20/05/2022 - 11:30
Imaging the supermassive black hole at the galactic center with the EHT
We present the first Event Horizon Telescope (EHT) observations of Sagittarius A* (Sgr A*), the Galactic center source associated with a supermassive black hole. These observations were conducted in 2017 using a global interferometric array of eight telescopes operating at a wavelength of λ = 1.3 mm. The EHT data resolve a compact emission region with intrahour variability. A variety of imaging and modeling analyses all support an image that...
José Luis Gómez, Rocco Lico, Guang-Yao Zhao, Ilje Cho, Antonio Fuentes, y Thalia Traianou