Seminars
Displaying 151 - 200 of 1242
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21/04/2022 - 12:30
SO Coloquio: Constraints on the origin of free-floating planets from the mass function The stellar mass function is a fundamental parameter to constrain star formation models. Although the stellar content has been extensively studied since Salpeter's first work in 1955, the study of the planetary mass regime is only now becoming feasible. I will present a recent census of the Upper Scorpius and Ophiuchus star- forming region, where we identified between 70 and 170 free- floating planets. This is by far the largest sample of... Dra. Núria Miret Roig |
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20/04/2022 - 12:30
Turning Trash into Treasure: How OH megamasers are contaminating next-generation HI surveys and what they can tell us about galaxy evolution OH megamasers (OHMs) are rare, luminous masers found in (ultra-)luminous infrared galaxies ([U]LIRGs). The dominant OH masing line at 1667 MHz can spoof the 1420 MHz neutral hydrogen (HI) line in untargeted HI emission line surveys. This ambiguity creates a potential source of “contamination” in HI surveys, particularly for next-generation surveys that will reach groundbreaking sensitivities and redshifts. In this talk, I will present... Dr. Hayley Roberts |
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07/04/2022 - 13:00
SO Webloquio: Measuring the Magnetic Fields of Exoplanets with Star-Planet Interactions Planets interact with their host stars through gravity, radiation and magnetic fields. For giant planets orbiting stars within ~20 stellar radii (=0.1 AU for a Sun-like star), magnetic star-planet interactions (SPI) are observable at a range of wavelengths with a variety of photometric, spectroscopic and spectropolarimetric techniques. At such close distances, planets orbit within the sub-alfvénic radius of the star, where magnetic interactions... Dr. Evgenya Shkolnik |
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31/03/2022 - 12:30
How the intracluster light is going to change your life! There are a huge number of astrophysical phenomena that remain barely studied due to the lack of large, multiwavelength and deep optical surveys. This is the Universe with the lowest density of stars, largely unseen by past large field surveys like the Sloan Digital Sky Survey (SDSS). For instance, only a handful of galaxy clusters have been observed with enough depth to witness the intracluster light (ICL), made up of stars that drift freely... Dr. Mireia Montes |
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24/03/2022 - 12:30
Is it possible to simulate time machines in a laboratory? General Relativity is the most succesful theory we have for describing gravitational phenomena. Its range of applicability is vast: from solar system scales to cosmological scales. It is well-known that GR allows the existence of time machines: devices that are able to generate Closed-Timelike-Curves (CTCs). Although these kind of objects are allowed in GR, most researchers believe that they cannot occur on macroscopic scales. However, it is... Gerardo Garcia |
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17/03/2022 - 12:30
Surprises from MAVEN at Mars: Aurora, meteor showers, and a new water loss paradigm The Mars Atmosphere and Volatile EvolutioN (MAVEN) spacecraft carries the Imaging Ultraviolet Spectrograph (IUVS) to study the Mars atmosphere and atmospheric escape. After more than two Mars years in orbit, IUVS has gained new insights on key phenomena at Mars including dayglow, nightglow, aurora, meteor showers, clouds, solar-planetary interactions and atmospheric evolution. In this presentation, I will highlight three key results... Dr. Nick Schneider |
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10/03/2022 - 12:30
The RoboPol Program: Optical Polarimetric Monitoring of Blazars Blazars are a subclass of Active Galactic Nuclei with relativistic jets pointing at us. For this reason the highly amplified polarized synchrotron emission from their jets dominates in the optical band. Typically, the electric vector position angle (EVPA) of the optical polarized emission in blazars varies in an erratic way. However, in rare cases the EVPA displays long, smooth and monotonic rotations. Being puzzled by this phenomenon missing a... Dr. Dimitriy Blinov |
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03/03/2022 - 12:30
The continuous rise of bulges out of galactic disks A tantalizing enigma in extragalactic astronomy concerns the chronology and driving mechanisms of the buildup of the central luminosity excess (bulge) in spiral galaxies like our Milky Way, i.e. in systems referred to as late-type galaxies (LTGs) in the Hubble classification scheme. The standard scenario envisages a two-phase galaxy formation process, with the bulge assembling first in a quick and violent quasi-monolithic episode, with the disk... Dr. Iris Breda |
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24/02/2022 - 12:30
SO Webloquio: Exploring the transient radio sky with the SKA and its precursors Radio astronomical observations probe particle acceleration in some of the most extreme environments in the Universe. For example, we can trace the relativistic jets produced by accreting black holes; observe flashes from hyper-magnetised neutron stars; and study the aftermath of stars that are ripped to shreds as they pass close to super-massive black holes. These events provide critical information about the extremes of the Universe, but they... Dr Jason Hessels |
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17/02/2022 - 12:30
The Africa Millimetre Telescope project - extending the EHT The Africa Millimetre Telescope (AMT) project led by the Radboud University and the University of Namibia aims to realise a new telescope on the Gamsberg mountain in Namibia to extend the existing network of telescopes that together form the EventHorizonTelescope (EHT). For the future of the EHT more independent nodes in the network are needed to increase the overal redundancy of the network and to improve the image quality and allow for time-... Dr. Marc Klein Wolt |
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10/02/2022 - 12:30
A high-fidelity sky mock of DESI galaxies in the LCDM cosmology By using N-body simulations in which different cosmologies have been assumed and by comparing them with large-scale galaxy surveys, we can constrain cosmological parameters, even ruling out some cosmological models. In this talk I will describe how we use the Uchuu simulation for this purpose. Uchuu is an N-body dark matter simulation that has been created by an international team of researchers from Japan, Spain, USA, Argentina, Australia,... Julia Ereza |
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03/02/2022 - 12:30
SO Webloquio: The Milky Way's young substellar population Young clusters and star forming regions are home to a large number of substellar objects with masses below the hydrogen-burning limit at 0.075 MSun. Most of our knowledge about their populations comes from nearby regions (d lower 400 pc), where we find consistent formation rates of 2-5 young brown dwarfs per 10 newborn stars. Brown dwarf theories, on the other hand, predict that high gas or stellar densities, as well as the presence of massive... Dra Koraljka Muzic |
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27/01/2022 - 12:30
La IAU más cerca que nunca The International Astronomical Union (IAU) has more that 13000 members. Each country pays according to a table that has to do with the number of people belongin to the IAU. But the IAU is not only a club of members but has a number of activities that are open to every member. In particular the IAU run 9 Symposia per year with topics relevant to current astrophysics. On years where there are a General Assembly on top of the 9 Symposia the IAU... Dr. José Miguel Rodriguez Espinoza |
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25/01/2022 - 12:30
Cosmological QUOKKAS: Proof of concept and early results on the Hubble Constant tension Distances are one of the most important yet difficult to get quantities in astronomy. Normally, astronomers use redshifts (which are relatively easy to measure) as distance measure, but this only works if one assumes that there is a relationship between redshift and distance. The relationship between redshift and distance was first observationally verified in the 1920s by Edwin Hubble. He found that the further away a galaxy was, the galaxy... Dr. Jeff Hodgson |
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20/01/2022 - 12:30
Astronomy for attaining sustainable development goals in Africa Education and its contribution to science, technology, and innovation are the key points for combating poverty in the long term. Education is also a key point for empowering girls and women, which is fundamental for achieving the United Nations Sustainable Development Goals (SDGs). Astronomy is a powerful tool to promote education and science but, in addition to that, it is also one of the leading sciences for bringing strong technological... Dra. Mirjana Povic |
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13/01/2022 - 12:30
Galaxy morphologies in multi-wavelength surveys In this talk I will present novel results obtained by using a combination of broad and narrow band optical photometry, from the J-PAS and S-PLUS surveys, in the determination and study galaxy of galaxies’ morphologies. In particular we used Morfometrika and GALFITM to recover non-parametric and parametric values to characterize galaxies’ shapes, as well as a deep learning method for the S-PLUS survey to classify galaxies into early and late type... Dra. Arianna Cortesi |
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11/01/2022 - 12:30
SO Webloquio: Active Galactic Nuclei as seen from the 7 X-ray eyes of eROSITA Active Galactic Nuclei (AGN) are not longer considered part of a small and exotic source population but are now widely accepted to play a significant role in the evolution of galaxies through cosmic time. However, even 20 years after the realization of the close link between the galaxies and the active SMBH that they host, the various mechanisms and the interconnection are not fully clear. Two complementary approaches are followed to deepen our... Dra. Mara Salvato |
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16/12/2021 - 12:30
Lighthouse Piercing Through the Storm Clouds in Massive Star Formation Massive stars play crucial roles in determining the physical and chemical evolution of galaxies. They shape their environment from early in their protostellar phase when they blast the surrounding with powerful jets, up until their violent deaths in the form of supernova. However, they form deeply embedded in their parental clouds, making it challenging to directly observe these stars and immediate environments. Notwithstanding, their massive... Dr Ruben Fedriani |
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09/12/2021 - 12:30
SO Webloquio: Unveiling the unseen magnetized universe with MeerKAT Galaxy clusters are known to harbour magnetic fields, the nature of which remains unresolved. Intra-cluster magnetic fields can be observed at the density contact discontinuity formed by cool and dense plasma running into hot ambient plasma, and the discontinuity exists near the second brightest galaxy, MRC0600-399, in the merging galaxy cluster Abell 3376 (redshift 0.0461). Elongated X-ray emission in the east–west direction shows a comet-like... Dr. James Chibueze |
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02/12/2021 - 12:30
The PUMA project. Mergers and feedback in local ULIRGs resolved by ALMA and MUSE+AO Galaxy mergers and interactions have a key role in the evolution of galaxies, specially at high-z when they were more common than today. Mergers trigger starbursts and AGN activity, which are both regulated by negative feedback processes, as well as can turn spiral galaxies into massive quiescent objects. The local counterparts of these major interactions and mergers are local ULIRGs (L(IR)/Lsun > 1e12) which, thanks to their proximity, allow... Dr. Miguel Pereira Santaella |
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25/11/2021 - 12:30
SO. Webloquia: AYA: projects and human resources in grants managed by the Spanish State Research Agency This presentation will review data and results of the national calls for projects and human resources managed by the AYA team in the AEI: research projects (PGC and Challenges), acquisition of scientific-technical equipment, proof of concept projects and strategic projects; and human resources, predoctoral hiring FPI, Juan de la Cierva training, Juan de la Cierva incorporation, Ramón y Cajal and R+D+I technical staff. Dra. Inmaculada Dominguez |
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23/11/2021 - 12:30
Search for MIlli-LEnses (SMILE) to discriminate between dark matter models Projects aimed at characterising dark matter properties make use of very different approaches. One such approach is to look for strong gravitational lens systems. Gravitational lensed images with angular separation on milliarcsecond scales probe gravitational lens systems where the lens is a compact object with mass in the range 10^6-10^9 solar masses, i.e a supermassive compact object (SMCO). This mass range is particularly critical for the... Dra. Carolina Casadio |
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18/11/2021 - 12:30
SO Webloquio: MOSAIC: the multi-object spectrograph for ELT MOSAIC will be the Multi-Object spectrograph for the ELT telescope. First light for this instrument is foreseen for 2031. MOSAIC is driven by scientific cases that include the study of the first galaxies in the Universe, the evolution of the large scale structure, resolved stellar populations beyond the Local Group, and the formation of exo-planets in different environments, among others. The instrumental concept includes visible spectrographs (... Dr Lidia Tasca |
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11/11/2021 - 12:30
SO Webloquio: Stellar winds and their effects on exoplanets As the wind outflows from a star, it permeates the interplanetary medium, interacting with any planet it encounters. In this talk I will review some recent works on winds of low-mass stars and discuss the impact stellar winds can have on surrounding exoplanets. Compared to the physical interactions known to take place between the solar wind and the solar system planets, the interaction between stellar winds and exoplanets can be significantly... Dra Aline Vidotto |
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04/11/2021 - 12:30
Identification and characterisation of emission line galaxies with J-PAS The Javalambre-Physics of the Accelerating Universe Astrophysical Survey (J-PAS) is expected to map thousands of square degrees of the northern sky with 56 narrow band filters (spectral resolution of R around 60) in the upcoming years. This resolution allows to study emission line galaxies (ELG) with equivalent widths of a few armstrongs. Meanwhile the Pathfinder J-PAS camera observed 1 deg^2 with the same photometric system than J-PAS, named... Gines Martinez Solaeche |
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28/10/2021 - 12:30
Seen the Unseen in Planetary Nebulae with High-dispersion Integral Field Spectroscopic Observations Planetary nebulae (PNe), the short-lived progeny of low- and intermediate-mass stars, may embed structures with varying kinematical, physical and chemical properties that disclose the rich variety of processes occurring during their formation. These structures hide in direct images, projected against the bright nebular emission, but the advent of high-dispersion integral field spectroscopic (HD IFS) observations provide the means to... Dr. Martín Guerrero |
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21/10/2021 - 12:30
Unveiling the dynamical stage of galaxy clusters through the intracluster light The intracluster light (ICL) is the most unexplored component of galaxy clusters. It is defined as a low surface brightness, extended emission composed by stars that are bound by the potential of the cluster but do not belong to any galaxy in particular. Simulations predict that minor and major mergers can mainly drive the formation of ICL, specially for z Dra. Yolanda Jimenez-Teja |
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14/10/2021 - 12:30
The miniJPAS survey: the galaxy populations in the miniJPAS cluster mJPC2470-1771 Galaxy clusters are one of the largest structures in the Universe. Due to the interaction among the galaxy members, they are a great laboratory to study the role of the environment in galaxy evolution. J-PAS survey will soon start to scan thousands of square degrees in the sky, and with its large great field of view (4.2 square degrees) and filter system (56 narrowband filters and 4 broadband filters in the optical spectral range) will provide... Julio Rodriguez Martin |
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07/10/2021 - 12:30
X-ray binary accretion states in AGN? Sensing the accretion disc of supermassive black holes with mid-IR nebular lines Accretion states, which are universally observed in stellar-mass black holes in X-ray binaries, are also anticipated in active galactic nuclei (AGN). This is the case at low luminosities, when the jet-corona coupling dominates the energy output in both populations. Previous attempts to extend this framework to a wider AGN population have been extremely challenging due to heavy hydrogen absorption of the accretion disc continuum and starlight... Dr Juan Antonio Fernández Ontiveros |
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16/09/2021 - 12:30
Precision cosmology: now what? The standard cosmological model (the LCDM model) has been established and its parameters are now measured with unprecedented precision. This model successfully describes observations from widely different epochs of the Universe, from primordial nucleosynthesis all the way to the present day. However, there is a big difference between modelling and understanding. The next decade will see the era of large surveys; a large coordinated effort of... Dra. Licia Verde |
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09/09/2021 - 17:00
SO Webloquio: A new look at our star: the Daniel K. Inouye Solar Telescope The Sun represents a template for much of our understanding of the workings of a "cool" star, and its proximity allows us to observe exquisite details at its surface, with current facilities routinely reaching resolutions of few hundreds of km on the solar disk. Yet, many questions still linger, in particular concerning the actual mechanism(s) that create and maintain a hot outer atmosphere (chromosphere, transition region and corona) as well as... Dr. Gianna Cauzzi |
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02/09/2021 - 15:00
The Lucy mission: exploring the unexplored Lucy is planned to launch in 2021 on a United Launch Alliance Atlas V launch vehicle, after which it will gain two gravity assists from Earth; one in 2022, and one in 2024. In 2025, it will fly by the inner main- belt asteroid (52246) Donaldjohanson, which was named after the discoverer of the Lucy hominid fossil. In 2027, it will arrive at the L4 Trojan cloud (the Greek camp of asteroids that orbits about 60° ahead of Jupiter), where it will... Dr. Adriana Ocampo |
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22/07/2021 - 12:30
Revealing cosmic magnetism with the Square Kilometre Array and its pathfinders Magnetism is an enigmatic but crucial element of our Universe. The structure and strength of magnetic fields are important for a full understanding of astrophysics over a tremendous range of scales: from stellar systems, to star forming regions, the properties and evolution of individual galaxies, galaxy groups and clusters, and even as a major element of the Cosmic Web. The Square Kilometre Array (SKA) promises to deliver a revolutionary view... Dr. George Heald |
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08/07/2021 - 12:30
SO Colloquium: TeV Halos and their connection to the Leptonic Cosmic Ray flux measured at the Earth The origin and propagation of cosmic rays (CRs) is one of the most important questions in astroparticle physics nowadays. CRs generated by known sources also serve as background to those putatively generated by more exotic phenomena such as dark matter. Apart from the known electrons of primary origin and positrons of secondary one, pulsars and sources powered by them are one of the main candidates to contribute to the total amount of CR... Dr. Rubén López-Coto |
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01/07/2021 - 12:30
SO Colloquium: Interstellar planetesimals: 1I/Oumuamua and 2I/Borisov Extensive surveys of extrasolar planets and of circumstellar disks around nearby stars show that planets and dust-producing planetesimals, similar to the asteroids, Kuiper belt objects and comets in our solar system, are ubiquitous around others stars. The planetesimal population of the young solar system was very numerous initially but the majority of the objects ended up ejected due to gravitational perturbations with the planets and other... Dra. Amaya Moro-Martín |
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24/06/2021 - 12:30
SO Webloquio: Asteroid sample return: A laboratory perspective The new generation of sample return missions from small bodies is delivering to us fresh witnesses from the early Solar System. In this context, laboratory studies play a double role: on one hand, in-depth laboratory analysis of retrieved samples using state-of-the-art techniques give us an unprecedentedly detailed look at the formation and evolution of organic materials in asteroids; on the other hand, in the laboratory we can perform... Dr. Rosario Brunetto |
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17/06/2021 - 12:30
SO Webloquio: Star-formation and accretion in galaxies from near to far: the LeMMINGs and eMERGE e-MERLIN legacy programmes Radio emission provides a uniquely powerful and unobscured probe of the two key physical processes underway in, and powering, galaxies and their evolution: Accretion on to their central SMBH, and star-formation processes. To explore these processes, and their role in galaxy evolution, we require very high resolution (sub-arcsecond or better), sensitive imaging at radio wavelengths across large samples of galaxies in both the local and distant... Dr. Rob Beswick |
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10/06/2021 - 12:30
SO Webloquio: Auroral Radio Emission in stars and exoplanetary systems In recent years, an interesting type of coherent radio emission has been detected in a wide variety of stars across the HR diagram, from hot magnetic A-B MS stars to Ultra Cool dwarfs: the Auroral Radio Emission (ARE), previously observed by spacecrafts in the magnetosphere of planets of the Solar System. Very different objects are showing the same phenomenon. What do they have in common? The first star with ARE was CU Virginis, an early type... Dr. Corrado Trigilio |
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08/06/2021 - 16:00
K-band interferometric imaging of the M-type Mira star ‘R Car’ The final stage of low to intermediate-mass stars, also known as the asymptotic giant branch (AGB), presents circumstellar envelopes (CSE); however the mechanisms that lead to the formation of these structures, at least in M-type AGBs, are still not well understood. In order to grasp the characteristics of the CSE, it has been found that the CO molecule plays an important role due to its stability against dissociation, making it a tracer of the... M.Sc. Abel Rosales-Guzmán |
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27/05/2021 - 17:00
SO Webloquio: A Spanish in Boulder The opportunity to lead the US National Solar Observatory (managed by AURA) since 2013 has allowed me to understand the differences in how R... Dr. Valentin Martínez Pillet |
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20/05/2021 - 12:30
SO WebLoquio: Regularly-spaced 8 micron cores as tracers of the earliest stages of star formation in the spiral arms of nearby galaxies Archival Spitzer Space Telescope images of most nearby spiral galaxies show prominent 8 micron emission cores when viewed with an unsharp mask technique. These cores have the IR colors of young star-forming regions, typically a million years old, behind several tens of magnitudes of optical extinction. They are usually invisible in optical images, and yet the sum of their masses divided by their likely age is comparable to the total star... Dr. Bruce Elmegreen |
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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 |
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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 |
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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 |
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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 |
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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 |
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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 |
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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 |
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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 |
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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 |