Seminars

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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
27/02/2020 - 12:30
Proper motion study of the Galactic Centre
Stellar proper motion studies in the centre of the Milky Way have been typically limited to the Quintuplet, Arches, and central parsec clusters. In this talk, I will present the primary results of a large-scale proper motion study of the central ~ 36' x16' of the Galaxy based on our GALACTICNUCLEUS survey (epoch 2015) combined with the HST Paschen-alpha survey (epoch 2008). This region of our Galaxy is not covered sufficiently by the existing...
Dr. Banafsheh Shahzamanian
20/02/2020 - 12:30
YOUNG RUNAWAY STARS
Most stars have spatial velocities within a few km/s of the average velocity of their surroundings and can be considered to be gravitationally trapped. There are, however, a small number of stars that move at velocities of tens or even hundreds of km/s with respect to their environment and that will eventually escape from there. The archetypal runaway stars are mu Col and AE Aur that escaped in opposite directions from the vicinity of the Orion...
Dr. Luis Felipe Rodriguez
18/02/2020 - 12:30
Evolution of statistical techniques in Astronomy
The requirement for more robust statistical tools is becoming increasingly higher owing to the demands of various large programmes and the technological advancement producing high-sensitive observations across the electromagnetic spectrum. Among the many existing analyses, the ones working on the time-series as set by the monitoring projects using single-dish/optical telescopes and those of spectral-line observations as rendered by ALMA/IFUs are...
Dr. Venkatessh Ramakrishnan
13/02/2020 - 12:30
From protostars to planets: the astrochemical link
Protostars accrete their material from the natal cloud through accretion disks. These disks are progressively dispersed by the recently formed star to form protoplanetary discs in which planets are born. Although this process takes a few million years, now we think that the final chemical composition of the gas and dust in the proto-planetary disk is to a large extent determined by the chemical evolution in the natal cloud. Determining the...
Dr. Asunción Fuente
11/02/2020 - 12:30
Experiments with MUSE data: Finding SN remnants & other curious sources
One of the ways of following up on the success story of CALIFA is to refine the spatial resolution, and MUSE is the tool for that. Its superb image quality allows for a different kind of science. While browsing through emission line images derived from MUSE datacubes, we have spotted a number of compact-looking sources with forbidden line emission ([OIII], [NII], [SII]) in excess of that typical of HII regions. NGC 4030, a late type spiral 30...
Dr. Roberto Cid Fernandes
06/02/2020 - 12:30
SO Colloquia: Extrasolar planets: recent advances and future challenges
Recently a group of scientists has confirmed the presence of water in the atmosphere of a super Earth orbiting in the habitable zone of its host star. But what what does this milestone represent in the search for life outside Earth? What do we mean by habitable? What do we really know about extrasolar planets, their internal structure or origins? What is a super Earth, the most common planet category know to date for which no example is found in...
Dr. Juan Cabrera
04/02/2020 - 12:30
Cosmic butterflies: the product of tempestuous stellar marriages
Planetary nebulae are some of the most strikingly beautiful astrophysical phenomena known, gracing many a glossy-paged, coffee-table book and earning them the nickname "cosmic butterflies". Classical stellar evolutionary theory states that all intermediate mass stars should produce a planetary nebula, forming as the star leaves the Asymptotic Giant Branch and evolves towards the white dwarf phase. While it remains the standard for astronomy...
Dr. David Jones
31/01/2020 - 12:30
NoiseChisel and Gnuastro: non-parametric detection and analysis of astronomical targets
Astronomical instrumentation has greatly advanced over the last 40 years: with digital detectors, space telescopes and +8m class ground-based telescopes for example. However, the signal-based detection paradigm (for example from Petrosian or Kron in the 1970s, mostly used as implemented in SExtractor from the mid-1990s) is still the dominant method of low-level data analysis: detection, segmentation and measurements or catalog production. In...
Dr. Mohammad Akhlagh
30/01/2020 - 12:30
Mirror-slicer Array for Astronomical Transients. A new Integral Field Spectroscopy mode for OSIRIS at GTC
MAAT (Mirror-slicer Array for Astronomical Transients) is proposed as a new mirror-slicer optical system that will allow the OSIRIS spectrograph at the 10.4 m GTC the capability to perform integral-field spectroscopy (IFS) over a seeing-limited field of view 14.20’' x 10'' with a slice width of 0.303''. MAAT will enhance the resolution power of OSIRIS by 1.6 times with respect to its 0.6'' wide long-slit. All the eleven OSIRIS grisms and VPHs...
Dr. Francisco Prada
23/01/2020 - 12:30
SO Colloquia: Extragalactic survey science in the 2020s: the role of radio continuum observations with the SKA
Extragalactic surveys in the 2020s will reveal the full diversity of the galaxy assembly process: from environment-dependent evolution to the build-up of mass inside galaxies, and with a complete accounting of all relevant processes/constituents ensured by multi-wavelength coverage. Observations at radio wavelengths carry a unique potential in that they can probe star-formation activity and cold gas content, i.e. place constraints on both galaxy...
Mark T. Sargent
15/01/2020 - 12:30
Public Surveys and new instrumentation for Calar Alto Observatory
The Calar Alto observatory (CAHA) is a key institution for the international astronomical community, for its highly competitive astronomical facilities (telescopes and instrumentation). From 2019 on, the current administration of CAHA includes the Junta de Andalucía as a new partner – replacing the Max Planck Gesellschaft -, and together with the Spanish National Research Council (CSIC) these two institutions manage the operation of the...
Dr. Jesus Aceituno
09/01/2020 - 12:30
Galaxy evolution and weak lensing studies in the J-PAS survey
During the next year, the J-PAS survey will start imaging the northern sky with a unique photometric system composed of 56 narrow and 4 broad bands. The peculiar configuration and strategy of this survey pursue to provide accurate low-resolution spectra or photo-spectra (FWHM~125 \AA) allowing us to obtain high-quality photometric redshifts (\sigma_z~0.003 for LRGs) for millions of galaxies across 8000 deg^2 of the sky. Recently, the J-PAS...
Dr. Luis Díaz García
19/12/2019 - 12:30
The SKA precursor telecope MeerKAT as a galaxy evolution explorer
MeerKAT is a radio telescope situated in South Africa's Karoo desert. It has recently been built as an SKA demonstrator and precursor telescope and was inaugurated in August 2018. Since then it has proven to be the world's most sensitive 20cm interferometer and is slowly moving towards standard operation. Thanks to its array layout MeerKAT is a superb telescope to observe in particular the HI line, hence tracing the most abundant atom in its...
Dr. Józsa Gyula István Géza
12/12/2019 - 12:30
NGC 7469 as seen by MEGARA: new results from high-resolution IFU spectroscopy
In this talk I will present highlights from our recent work about the analysis of high-resolution (R ~ 20 000) GTC/MEGARA integral-field unit spectroscopic observations, obtained during the commissioning run, in the inner region (12.5arcsec×11.3arcsec) of the active galaxy NGC7469, at spatial scales of 0.62 arcsec. We explore the kinematics, dynamics, ionisation mechanisms and oxygen abundances of the ionised gas, by modelling the Hα-[NII]...
Dr. Sara Cazzoli
10/12/2019 - 12:30
SO-IAA Colloquium: Unveiling the nature of planetary systems
The burgeoning field of exoplanets has yielded thousands of discoveries, which collectively have the potential to help us better understand our place in the Universe. Every month more and more planetary systems are being discovered,some of them in highly exotic configurations never observed previously. The combination of different techniques and studies are needed to unveil the real nature of these planetary systems. In this seminar, I will...
Dr. Francisco Pozuelos
05/12/2019 - 12:30
Gaia mapping mission and science of Solar System Objects
I will present the generalities of the Gaia surveying mission, and current status. I will then discuss the improvement brought by Gaia over its 5 years and more of mission—starting with DR1—for the science of asteroids and other SSOs; and focusing especially on the astrometry and dynamics of asteroids. After reminding generalities on SSO observations by Gaia - and some of their peculiarities, we present some of the advances obtained from the...
Dr. Daniel Hestroffer
02/12/2019 - 12:30
Molecular outflows: evolution, structure and angular momentum
We present a theoretical model in order to explain the formation and the evolution of the molecular outflows associated to protostars. In this model, we assume that the molecular outflow is a thin shell formed by the interaction between a fast stellar wind and a rotating cloud envelope in gravitational collapse. We obtain a set of partial differential equations, these equations are space and time dependent, and describe the physical properties...
Dr. Alejandro López Vázquez
28/11/2019 - 12:30
SO-IAA Colloquium: Recent advances about the exoplanetary exospheres
The upper atmosphere of a planet plays a key role at protecting the lower altitudes from the effects of energetic stellar EUV and soft X-ray photons and keV-energy precipitating particles. Through a variety of transport processes, the upper atmosphere also participates in the net loss of a planet’s bulk composition into space. As such, the physics and chemistry occurring in the upper atmosphere influence the evolution of a planet over its...
Antonio García Muñoz
26/11/2019 - 12:30
Inverse Compton emission revealed by observations up to TeV energies of GRB 190114C
The hunt for Gamma-Ray-Bursts (GRBs) at very high energy (VHE) started more than 20 years ago. A hint of emission was already claimed by Milagrito from the observations of GRB 970417. On 19 of January the Major Atmospheric Gamma Imaging Cherenkov (MAGIC) clearly detected GRB 190114C above 0.2 TeV. This is the first highly significant detection (over 50sigma reached in the first few tens of minutes after the burst) of a GRB at VHE. GRB190114C...
Dr. Elena Moretti
19/11/2019 - 12:30
METIS instrument: the IMAGER and the SCAO
METIS is one of the three first instruments for the European Extremely Large Telescope (ELT), Europe’s next-generation ground-based telescope for optical and infrared wavelengths which is currently under construction at the ESO site at Cerro Armazones in Chile. METIS is the Mid-infrared ELT Imager and Spectrograph. This instrument will offer imaging, coronagraphy and medium-resolution spectroscopy over the full wavelength range from 3 to 14...
Dr. Concepción Cárdenas
14/11/2019 - 12:30
SO-IAA Colloquium: Outflows and their feedback effect in galaxies
Galactic outflows are an essential component of galaxies' lifecycle. They regulate star formation and can even totally quench star formation in galaxies, hence transforming star forming galaxies into passive systems. I will review the properties of galactic outflows, their multi-phase nature, their driving mechanism, both in normal star forming galaxies and in galaxies hosting Active Galactic Nuclei, both in the local Universe and in...
Dr. Roberto Maiolino
12/11/2019 - 12:30
Study of the diversity of AGN dust models
The dust component of active galactic nuclei (AGN) produces a broad infrared spectral energy distribution (SED), whose power and shape depends on the fraction of the source absorbed, and the geometry of the absorber respectively. This emitting region is expected to be concentrated within the inner ∼5 pc of the AGN which makes almost impossible to image it with the current instruments. The study the infrared SED by comparison between infrared AGN...
Dr. Omaira González-Martín
07/11/2019 - 12:30
SO-IAA Colloquium: Characterization of (exo)Planetary Atmospheres
Characterization of planetary atmospheres has always been a challenge. While the next generation of facilities, such as ELT, JWST, and ARIEL, will improve our understanding of planetary atmospheres, the number of well-characterized exoplanet atmospheres is expected to remain limited. Large-scale simulations assist us with this shortcoming by predicting the diversity of the planetary atmospheres, connecting the spare observational measurements,...
Dr. Karan Molaverdikhani
31/10/2019 - 12:30
SO-IAA Colloquium: Neutral and molecular gas outflows as tracers of the impact of radio jets
Our view of the gas and its physical conditions in the central region of AGN has been enriched by the discover of fast and massive outflows of HI and molecular gas. These outflows can be driven by radiation/winds but also by the interaction of the radio plasma with the ISM. Understanding the origin and quantifying their impact requires to trace their location and derive their physical conditions (density of the gas, mass, mass outflow rate and...
Dr. Raffaella Morganti
29/10/2019 - 12:30
Nebular HeII emission from spatially resolved metal-poor star-forming galaxies
Nebular HeII1640,4686 emission, observed to be more frequent in high-z galaxies than locally, is indicative of far harder ionizing spectrum than that seen in nearby systems. Star-forming galaxies with lower metal content tend to have a larger nebular HeII intensities compared to those with higher metallicities. This agrees with the expected harder spectral energy distribution at the lower metallicities typical in the early universe. Theoretical...
Dra. Carolina Kehrig
24/10/2019 - 12:30
ANALOGUES OF HIGH REDSHIFT GALAXIES: DISENTANGLING THE COMPLEXITY OF THE GREEN PEAS
Young low-mass galaxies with extreme emission-line properties are ubiquitous at high redshift and they are believed to play a key role in cosmic reionisation and the early growth of galaxies at z>4-6. However, a detailed characterisation of their physical properties, critical for a better understanding of these two outstanding problems, is yet not possible. A unique population of lower-z analogues of these primeval systems, dubbed Green Pea (GP...
Dr. Ricardo Amorin
23/10/2019 - 12:30
Molecular spectroscopy at high resolution for everyone
Molecular observations at high resolution is being revolutionized by the success of ALMA and the upcoming advent of SKA. In this talk I will explain the recent progress in the field of molecular observations in the central regions of galaxies and the big steps that we are currently making in the use and understanding of molecular tracers as a proxy to buried physical processes in active galaxies. I will show some preliminary results from the...
Dr. Sergio Martín Ruiz
22/10/2019 - 12:30
Data mining Gaia DR2: the quest for Pre-Main Sequence Stars (and their discs)
As the birth-sites of planets, protoplanetary discs have become the object of intense study during the last years. Constraining their typical lifetimes, masses and/or sizes is crucial to understand the process of planet formation. These objects are a natural by-product of early stellar evolution, and therefore a high fraction of Pre-Main Sequence Stars (PMS) are surrounded by a protoplanetary disc. The current census of PMS (and discs) has been...
Dr. Héctor Cánovas
17/10/2019 - 12:30
SO-IAA Colloquium: What's is the metallicity of cool dwarf stars?
Cool dwarfs are the most numerous stars in the Galaxy and they account for most of its baryonic mass. However, they are likely the least understood main sequence stars. Their complex atmospheres, due to their low temperatures and high surface gravities, have made their spectroscopic study a hard task. Until recently, their basic physical properties, such as radii and mass, were poorly constrained due to the lack of empirical data. Stellar...
Bárbara Rojas-Ayala
10/10/2019 - 12:30
THE INNER DEBRIS OF SN1987A: MOLECULAR AND DUST EMISSION
The supernova SN1987A in the Large Magellanic Cloud, together with new instrumentation like ALMA, offers an unprecedented opportunity to tackle fundamental issues of supernova explosions. Large masses of molecules and dust have been formed in its inner debris over the last 25 years. Recently developed tomographic techniques have allowed to obtain 3D-images of its molecular emission. Also, high-resolution images of dust emission have recently...
Prof. Jon Marcaide
07/10/2019 - 12:30
SO Colloquia: FPGAs in space: current experiences, future challenges and opportunities
FPGAs are key components in space equipment due to their versatility and performance to implement digital functions. They are embarked in satellites and used in many applications; such as observing the earth, provide telecommunications and navigation services as well as to contribute to science and explore the wider Universe. The FPGAs face very different conditions in space compared to the terrestrial applications, especially due to the...
Merodio Codinachs
04/10/2019 - 12:30
Cúmulos Jóvenes: eclosionando, moviéndose, volando
En las últimas dos décadas, nuestro conocimiento de los cúmulos estelares jóvenes, ha progresado rápidamente del uso de imágenes estáticas con cada vez mayor calidad, hacia mapas de movimientos en seis dimensiones (posiciones, velocidades), que están cambiando muchas de nuestras ideas de cómo los cúmulos estelares surgen de los complejos de nubes moleculares. Conforme nos movemos de escalas de parsecs a hectoparsecs, ahora vemos a los cúmulos...
Dr. Carlos G. Román Zúñiga

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