Webinars 347

Since 2011 we promote webinars which are an important aspect of our personnel development. This allows collaborators anywhere in the world to join seminars about the latest developments in several astronomical and technical fields. Webinars are presented in english and announced to a mailing list. Click here if you want to subscribe.

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Speakers 315

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Scheduled webinars 07

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04/11 - 02:00 pm BRT

Dragan Huterer ( University of Chicago )

Probing the Universe with Dark Energy Survey: a Holistic View

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11/11 - 02:00 pm BRT

Nina Hemitschek ( Vanderbilt University )

Rubin Observatory Community Brokers - real-time astronomical alert processing

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18/11 - 11:00 am BRT

Andreu Font-Ribera ( Universitat de Barcelona )

Studying the expansion of the Universe with quasar spectra from the Dark Energy Spectroscopic Instrument

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25/11 - 11:00 am BRT

Francisco Förster ( Universidad de Chile )

The universe in a stream: challenges and progress of the ALeRCE broker

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02/12 - 02:00 pm BRT

Troy Raen ( University of Pittsburgh )

Pitt-Google Astronomical Alert Broker

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09/12 - 02:00 pm BRT

David Trilling ( Northern Arizona University )

SNAPS: The Solar System Notification Alert Processing System

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16/12 - 02:00 pm BRT

Richard Kron ( Fermilab )

News from the Dark Energy Survey

Past webinars 340


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28/10 - 06:00 pm BRT

Anais Möller ( Swinburne University of Technology )

Fink broker enabling time-domain science with Rubin Observatory


In this decade, Vera C. Rubin Observatory will obtain high-resolution optical images of the Southern Sky at unprecedented depths. Rubin public alert stream will communicate the detection of millions of potential transient objects every night. The key to use this stream is to be able to select promising transients and to automatically connect them to teams and observing facilities. I will introduce Fink, a broker developed on high-end technology and designed for fast and efficient analysis of big data streams. It has being chosen to process the full Rubin optical time-domain data stream. Fink enables the selection of promising transients by providing preliminary classifications based on machine learning algorithms and combining information from catalogues and surveys. Within minutes, Fink is able to communicate these candidates to teams and follow-up facilities. We are already deployed using ZTF data and have ongoing collaborations in a wide range of science including supernovae and multi-wavelength/messenger events as kilonovae and Gamma Ray Burst afterglows.

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21/10 - 02:00 pm BRT

Thomas Matheson ( NOAO )

ANTARES, An Astronomical Time-Domain Event Broker


ANTARES is a time-domain event broker developed and operated by the NSF\\\'s National Optical-Infrared Astronomy Research Laboratory. It provides a platform for community-driven processing of alerts. After ingesting alerts, the ANTARES system cross matches them with extant astronomical catalogs and annotates them with additional contextual information, including any past history of alerts at that location. The ANTARES processing pipeline then applies filters, which can be user-supplied, to sort and classify alerts based on features, both from the alert itself and the contextual information. These sorted subsets are then distributed to interested astronomers. I will provide an overview of the system including its performance in processing the public Zwicky Transient Facility alert stream, our scaling tests that will ensure we are ready for the Vera Rubin Observatory\\\'s Legacy Survey of Space and Time, and demonstrate how anyone can write a filter and begin getting personalized alerts now.

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14/10 - 11:00 am BRT

Héctor Gil-Marín ( Universitat de Barcelona )

Cosmology from galaxy redshift surveys: current results and future techniques


In the first part of this talk I will review the state-of-the-art techniques used for the analysis of the results of the BOSS and eBOSS galaxy survey maps. In the standard approach galaxy clustering measurements from spectroscopic surveys are compressed into baryon acoustic oscillations (BAO) and redshift space distortions (RSD) measurements, which in turn can be compared to cosmological models. I will present the main cosmological results of BOSS-eBOSS which represent the state-of-the art cosmological measurements from galaxy spectroscopic surveys. In the second part of the talk I will introduce the on-going redshift survey DESI, and will present some novel techniques that will be used in this up-coming dataset to make the cosmological analysis blind and to extract further extra information beyond BAO and RSD signals.

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07/10 - 11:00 am BRT

Robert Morgan ( University of Wisconsin-Madison )

Cosmological Spectacles: Novel Deep Learning Detection Strategies for Strongly Lensed Transients


The current tension on the measured value of the expansion rate of the Universe today (H0) has pushed the cosmological community to pursue more measurement techniques and larger datasets. One such technique, the characterization of systems with gravitationally lensed supernovae, is of particular interest in the Rubin Observatory era for two reasons: (1) thousands of these systems will be detectable by the Rubin Observatory when only a handful exist in current datasets, and (2) each identified system offers an independent measurement of H0, enabling high precision over the 10-year Legacy Survey of Space and Time. In this talk, I present a novel deep learning architecture for lensed supernovae detection that identifies more lensed supernovae (90 percent of the expected population) than any other previously proposed method.

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30/09 - 10:00 am BRT

Barak Zackay ( Weizmann Institute of Science )

Exact astronomical image processing


In this talk, I would explain from basic principles the theory of detecting point sources in ensembles of astronomical images (Zackay & Ofek 2017 a, b) and the theory of \\\'proper image subtraction\\\' (also known as ZOGY) (Zackay, Ofek & Gal-Yam 2017). Then, time permitting, I would explain future efforts to extend these operations to undersampled images in preparation for the ULTRASAT space mission, led by the Weizmann institute of science.

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16/09 - 11:00 am BRT

Tassia Ferreira ( UFES )

Cosmic shear covariance matrix comparison


Covariance matrices are among the most difficult pieces of end-to-end cosmological analyses. Advancements in cosmological surveys lead to larger data vectors and, consequently, increasingly complex covariance matrices, whose number of elements grows as the square of the size of the data vector. The most certain and forward way of comparing these matrices is in terms of their ability to reproduce cosmology, that is, by performing a full Bayesian analysis. This approach, however, can be very time consuming and computationally demanding. Using the concept and construction of compression schemes, which have become increasingly popular, we propose a fast and reliable way of comparing covariance matrices via a fast Monte Carlo simulation. In this talk, I will give an overview of cosmic shear, before moving on to the topic of covariance matrices. I will then motivate the use of compression schemes and show that they can be powerful tools for comparing covariance matrices. I will conclude by showing some of the exciting results obtained with our python algorithm.

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09/09 - 02:00 pm BRT

Claudia Bauzer Medeiros ( Unicamp )

O ecossistema de Ciencia Aberta – compartilhando universos em mini, macro, mega e exa escalas.


A Ciência Aberta é um movimento mundial cujo principal objetivo é permitir que pesquisadores em qualquer lugar do mundo possam colaborar por meio do compartilhamento dos seus resultados de pesquisa - como por exemplo dados, software, modelos ou publicações. Os principais valores associados são inclusão, transparência, e pesquisa confiável e reprodutível. A astronomia é uma das áreas em que este movimento se destaca, pela ampla publicação de catálogos, pelo compartilhamento de dispositivos e software, e pelas publicações envolvendo uma grande quantidade de pesquisadores do mundo inteiro. O que falta fazer? Como outras áreas do conhecimento vêm tratando do assunto? Práticas de Ciência Aberta estão se tornando obrigatórias em um grande número de países e, inclusive, exigidas para submissão de projetos a agências de fomento de todo mundo. A palestra vai apresentar o movimento de Ciência Aberto a partir das diretrizes de 2021 da Unesco, e dar exemplos de como estão sendo seguidas, incluindo obstáculos para sua realização plena.

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26/08 - 11:00 am BRT

Edison Cesar Santos ( UFES )

Charged black hole and radiating solutions in entangled relativity


The main goal of this seminar is to present a black hole solution in a new theory of gravity, which we call Entangled Gravity. In this theory, spacetime itself cannot exist without the presence of matter. To motivate the study of new theories of gravity, I will start by giving a broad review of Einstein\\\\\\\'s general relativity (GR) and recall some of its successes and failures. As we impose modifications to GR, Entangled Gravity will naturally appear as an adequate alternative to explain the Universe. In the context of this new theory, a black hole solution will be proposed which is indistinguishable from the usual Schwarzschild black hole solution from GR.

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12/08 - 11:00 am BRT

Hugo Camacho ( UNESP )

Cosmological results from the first three years of observations of the Dark Energy Survey - an overview


The Dark Energy Survey (DES) has recently released cosmological analyses from its first three years (DESY3) of observations, imaging 5000 square degrees in the southern sky. We review the novel advances in the methodology required to extract and combine galaxy clustering and weak lensing information in the DESY3 data. We present some of the main results, focusing on the combination of three two-point correlation functions, the so-called 3×2pt, and the BAO feature detection analyses, and discuss its cosmological implications.

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05/08 - 11:00 am BRT

Bruno Morgado ( Observatório Nacional )

An in-depth view of Centaur (10199) Chariklo and its rings from stellar occultations


The Centaur (10199) Chariklo is a small body moving in an elliptical orbit between Saturn and Uranus. In 2013, Braga-Ribas et al. (2014) discovered two rings orbiting this Centaur using stellar occultation, and this was the first time that rings were observed around a small body. In this talk, I will present the obtained results from stellar occultations by Chariklo observed between 2013 and 2020. I will present the global shape of Chariklo\\\\\\\\\\\\\\\'s rings system and the 3D shape of Chariklo\\\\\\\\\\\\\\\'s main body. The parameters obtained in this work should be useful for constraining dynamical models of Chariklo and its rings and provide new insights into the formation and evolution of this system.

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29/07 - 11:00 am BRT

Jacques Lepine ( Universidade de São Paulo )

The role of the co-rotation resonance in the Galactic disk and its influence on the Sun and stars of the Solar neighborhood

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22/07 - 11:00 am BRT

Carlos Bengaly ( (Observatório Nacional) )

Observational tests of the fundamental hypothesis of Cosmology


The standard model of Cosmology (SCM) consists on the LCDM model, which is dominated by cold dark matter and Cosmological Constant. Although this model provides the best description of cosmological observation thus far, the nature of these two components remain unveiled. Therefore, there is an urge to develop models to explain them, but on top of that, we need to put the fundamental hypotheses underlying the SCM under scrutiny. After all, statistically significant evidence of departure of these hypotheses may lead to complete reformulation of the SCM. In this talk, I present some observational tests I carried out with this goal. I will talk about some observational tests of the Cosmological Principle - namely, the assumption of large-scale homogeneity and isotropy of the Universe - using a variety of cosmological data. In addition, I will show results obtained by probing the validity of two fundamental assumptions which these data relies upon: the constancy of the absolute magnitude of Type Ia Supernovae, and the current temperature of the CMB.

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15/07 - 11:00 am BRT

Davide Perna ( INAF Rome Astronomical Observatory )

Near-Earth Asteroids: Risks and Opportunities


The proximity of near-Earth asteroids (NEAs) allows us to investigate the physical properties of small bodies down to the decameter-scale. A dedicated space mission to such small NEAs will be key to shed light on accretion mechanisms that took place in the protoplanetary disk. Extended ground-based observations will be also fundamental to fully characterize the physical diversity of the NEA population, whose discovery rate is exponentially growing in recent years. Besides its relevance for our understanding of the solar system and planetary science, NEA investigation is also essential to assess the potential exploitation of the asteroidal mineral resources in the near future, as well as to increase our capacity of mitigating the asteroid threat of collision with the Earth. I will present and discuss some recent results and future perspectives related to the science of NEAs, with a particular focus on small-sized objects.

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08/07 - 11:00 am BRT

Denny Lee ( Databricks )

Bringing Reliability to your Data Lake with Apache Spark and Delta Lake


Apache Spark has become the de-facto open-source standard for big data processing for its ease of use and performance. The open-source Delta Lake project improves Spark’s data reliability, with new capabilities like ACID transactions, Schema Enforcement, and Time Travel. This helps to ensure that data lakes and data pipelines can deliver high-quality and reliable data to downstream data teams for successful data analytics and machine learning projects. Join us to learn how Apache Spark 3.0 and Delta Lake enhance Data Lake reliability.

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01/07 - 02:00 pm BRT

Wagner Corradi ( Universidade Federal de Minas Gerais / LNA )

Impacto da ciência realizada com os telescópios e instrumentos gerenciados pelo LNA


O Laboratório Nacional de Astrofísica (LNA) é a Unidade de Pesquisa do Ministério de Ciência, Tecnologia e Inovação (MCTI) responsável por planejar, desenvolver, promover, operar e coordenar os meios e a infraestrutura para fomentar, de forma cooperada, a Astronomia Observacional Brasileira. O LNA possui a importante tarefa de gerenciar o Observatório do Pico dos Dias (OPD) e a participação brasileira nos observatórios internacionais Gemini (Norte, no Havaí e Sul, no Chile) e SOAR, no Chile, além de outras iniciativas como o PanEOS, LSST e LLAMA, por exemplo. Além disso, participa ativamente na concepção e construção de novos instrumentos astronômicos e sistemas periféricos. Pretendemos apresentar os avanços na instrumentação e o impacto da ciência realizada com os telescópios gerenciados pelo LNA, a partir de uma perspectiva histórica, nesses 35 anos de sua existência.

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24/06 - 09:00 am BRT

Dalya Baron ( Tel Aviv University )

Machine learning in astronomy: past, present, and future


Machine Learning and Deep Learning have revolutionized many domains, and have sparked a burst of interest in astronomy as well. Astronomical datasets, being large, rich, and consisting of the beautifully complex ingredients of our Universe, seem to offer the perfect testbed for such tools. Past, ongoing, and future surveys have provided or are expected to provide multi-color and multi-temporal observations of hundreds of millions of stars and galaxies in our Universe. The application of Machine Learning tools to these datasets may offer new and exciting opportunities, but it also raises several questions. Will Machine Learning revolutionize the field of astronomy as well? Will it have a dramatic impact on our data processing pipelines, on the models we deduce from the data, or on the types of scientific questions that we ask? In this talk I will review different types of Machine Learning algorithms and will present some example applications of these tools to astronomical datasets. I will describe the current state of the field, focusing on the challenges we face. I will finish by proposing an approach that might help us harness the full potential of these tools in the future.

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10/06 - 02:00 pm BRT

Robert Nikutta ( NOIRLab )

Astro Data Lab - An open-access and open-data science platform


The Astro Data Lab (https://datalab.noirlab.edu), or Data Lab for short, is an astronomical science platform developed at NOIRLab. It is open and free to all who are interested in astronomy, data science, and education efforts. Launched 4 years ago to enable remote access and analysis of survey data products generated by NOAO\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\'s telescopes, such as the Dark Energy Survey, Data Lab now serves almost 100 TB of catalog data from all major NOIRLab-operated facilities, plus high-value external datasets (e.g. Gaia, unWISE/AllWISE, SDSS, and others). It also provides access to over 2 PB of images. As a science platform Data Lab combines big data holdings with a number of very useful data services, and with the powerful idea of remote analysis through a Jupyter notebook server. Data Lab user accounts come with a generous allocation of remote storage for files and personal databases. In this seminar I will introduce the concepts that underlie a science platform, and highlight the data services Data Lab is able to offer thanks to the co-location of big data and compute capacities. I will then discuss some of our current new developments, for instance to serve data products from massively-multiplexed spectroscopic surveys such as SDSS and DESI. Finally I would also like to discuss with everybody some of the challenges and pportunities for making science platforms more unified in terms of user experience, and more interoperable from the operators\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\' perspective. Time permitting, I can show a brief live demo of Data Lab.

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03/06 - 12:00 am BRT

Public Holiday ( Corpus Christi )

No event scheduled

On that day there will be no LIneA webinar. Corpus Christi is a public holiday in some countries, including Brazil.

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27/05 - 11:00 am BRT

Willian Vieira de Abreu ( Universidade Federal do Rio de Janeiro )

Divulgação científica na astronomia: experiências e perspectivas


A Astronomia e ciências afins despertam o interesse da população, oferecendo um grande potencial de estimular jovens a ingressarem em carreiras científicas e despertarem o interesse por temáticas relacionadas. Dentro desse contexto, a divulgação científica pode exercer um importante e necessário papel de impulsionadora de novos talentos e de facilitadora entre ciência e sociedade, podendo inclusive possibilitar um primeiro contato com as ferramentas técnicas da área. Mas o que os jovens pensam sobre a ciência? E os comunicadores da ciência: o que pensam e pesquisam? Discutiremos essas e outras questões a partir de estudos acadêmicos e de dados do Instituto Nacional de Comunicação Pública da Ciência (INCT-CPCT), bem como de pesquisas nacionais e internacionais.

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20/05 - 11:00 am BRT

Thaisa Storchi Bergmann ( Universidade Federal do Rio Grande do Sul )

The relation between Supermassive Black Holes and their host galaxies probed by the MaNGA-SDSS survey


Supermassive Black Holes (SMBHs, masses of 106 – 109 MSun) inhabit the nucleus of most galaxies in the Universe. Although not even light can escape their event horizon, when capturing mass, they become the most efficient energy generators in the Universe via the emission of radiation, winds and jets by an accretion disk that surrounds them in active galactic nuclei (AGN). These are the so-called AGN feedback processes required by galaxy evolution models in order to reproduce the mass distribution of galaxies in the Universe. Nevertheless, the actual processes involved are not yet well constrained by observations. In this talk, I will discuss studies that provide constraints to these processes via MaNGA-SDSS observations of a sample of AGN and a matched control sample of non-active galaxies. These observations have been used to investigate answers to two of the most important questions on the relation between SMBHs and their host galaxies: (I) What are the necessary conditions for triggering/maintaining AGN in galaxies? (II) Which is the impact of the nuclear activity on the host galaxy and its environment?

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13/05 - 11:00 am BRT

Francesco Valentino ( University of Copenhagen )

The life and death of massive galaxies


The majority of the stars in the local Universe belong to massive, red, spheroidal, old galaxies that died several billion years ago, ceasing their active formation of new stars. In our current view, these galaxies experienced an intense burst of growth immediately followed by a sudden death early in the history of the Universe, so that we routinely observe a numerous population of such dead cosmic giants already in place 10 Gyr ago at z~2 comfortably reproduced by many galaxy formation models and simulations. However, the coherent scenario that we have been building during the last 15 years has been recently shaken by the discovery of the existence of massive dead galaxies already at z~4, only 1.5 Gyr after the Big Bang. How is it possible to assemble 100 billion Suns in such a short time, given the expected theoretical limits on the sustainable star formation rate? What can we learn about such a dramatic production of stars? What are the progenitors of these quiescent galaxies at z>4? And why do these cosmic giants die so early in the history of the Universe? Here I will present the results of a spectroscopic campaign targeting massive quiescent galaxies at z~4. These include a compact system at z=4.01 with a measured stellar velocity dispersion fully consistent with z~2 objects, showing that quiescent galaxies can be remarkably mature also from a dynamical standpoint. The absence of nebular emission lines and the lack of far-infrared detections confirm a suppressed star formation. From the joint modeling of the spectra and the SEDs, we derive stellar masses of log(Mstar/Msun)~11, placing these galaxies >1-2 dex below the main sequence. Such modeling suggests that these sources experienced a strong (SFR~1200-3500 Msun/yr) and short (~50 Myr) burst of star formation in their past, properties reminiscent of the population of sub-mm galaxies (SMGs) generally indicated as candidate progenitors. We thus compare the comoving number densities and the expected properties of the progenitors of our and other samples in the literature with observations of z>4 SMGs. We find a fair agreement between these two populations only for the deepest sub-mm surveys detecting the most extreme starbursts, but also more normal galaxies. Exploring the Illustris-TNG simulation, we do retrieve populations of quiescent galaxies at z~3-3.5 with number densities and properties in rough agreement with the observations, but in increasing tension at higher redshifts. We find that not all the progenitors of z~4 quiescent galaxies in the simulation shine as bright SMGs in their past and, conversely, not all bright SMGs quench by z~3, supporting the observational evidence and suggesting the existence of different paths to form massive galaxies in the early Universe.

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07/05 - 03:00 pm BRT

Michael Blanton ( University of New York )

Galaxies Near and Far with the Sloan Digital Sky Survey


I will discuss the recent work of the Sloan Digital Sky Survey on cosmology and galaxy evolution, based on the observations from its fourth phase, which completed its six year program on the morning of January 21, 2021. This spectroscopic survey mapped the Milky Way galaxy, ten thousand nearby galaxies, and finished the largest three-dimensional map of the universe to date. I will describe a sampling of what we have learned, focusing on: tests of the \\\\\\\"simplest\\\\\\\" model of the universe\\\\\\\'s expansion (which seems to be the right one); observations of star-formation and the flow of gas within galaxies; and on the formation history and migration of stars within our own galaxy.

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29/04 - 02:00 pm BRT

Samuel Schmidt ( University of California Davis )

Rubin Obs. Dark Energy Science Collaboration Photometric Redshifts: Challenges and Opportunities


In the era of large area, deep imaging surveys the ability to follow up even a small fraction of objects with spectroscopy is prohibitively expensive. As a result, these surveys will need to rely on other means to determine the distance to objects and turn the observed 2D sky into a fully three-dimensional map of the Universe using only the limited information available from broad band fluxes. In this talk I will discuss the challenges inherent in estimating redshifts for cosmology measurements in the Rubin Observatory Dark Energy Science Collaboration (DESC), which has extremely stringent requirements on knowledge of both individual galaxy redshifts and the redshift distribution of ensemble collections. I will discuss the end-to-end photometric redshift pipeline being developed by DESC, from simulated catalogs, to template and machine learning-based estimation algorithms, to systematic calibrations, that will enable the cutting edge science of the coming decade.

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22/04 - 11:00 am BRT

Allan Alves & Denise Köche ( Agência Propósito )

O que pensa e o que busca a comunidade científica na chegada do LSST


No webinar, a empresa de comunicação Propósito dividirá aprendizados sobre a pesquisa e os workshops realizados com a comunidade científica junto ao LIneA durante o mês de Março de 2021, com as percepções em relação aos impactos e expectativas do uso de big data na astronomia brasileira, assim como as barreiras e expectativas para o futuro.

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15/04 - 11:00 am BRT

LIneA Workshop ( LIneA )

On the Future of Data Centers and eScience Institutes: Celebrating LIneA’s 10th Anniversary

This workshop will bring together representatives of some of the more important data centers, eScience institutes and IT companies to discuss current solutions and new technological trends as data volumes from modern experiments such as LSST, Euclid and SKA continue to grow. The workshop will take place remotely April 13-15, 2021. Inquiries can be sent to workshop2021@linea.gov.br.

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08/04 - 11:00 am BRT

Santiago Àvila ( Universidad Autónoma de Madrid )

The effect of the galaxy-halo connection on galaxy clustering in the advent of stage-IV experiments


Studies of the Large-Scale Structure via galaxy clustering is a fundamental observational pillar of the standard model of cosmology, LCDM. As we enter the era of sub-percent precision cosmology, we need to understand very well the connection between the dark matter halos and the observed galaxies ir order to obtain unbiased cosmological parameters. In this talk I will analyse all the assumptions that enter into the Halo Occupation Distribution (HOD) model to understand how they can affect the clustering of galaxies, with a focus on Emission Line Galaxies (ELGs), key to the next generation of experiments. I will study the shape of the mean halo occupation curves, the probability distribution function of the satellite galaxies and the position and velocity profiles of the satellite galaxies around the halo centers. Later, I will fit the HOD model to ELG data from the completed extended Baryonic Oscillation Spectroscopic Survey (eBOSS) under different assumptions. Finally, I will show what effect the galaxy-halo connection could have on cosmological constraints and will discuss its relevance in the context of future surveys such as Euclid or DESI.

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01/04 - 11:00 am BRT

Tilman Troester ( Royal Observatory, Edinburgh )

Cosmology with the Kilo-Degree Survey


I will present the recent cosmological analyses of weak gravitational lensing observations from the Kilo-Degree Survey (KiDS-1000), with redshift-space galaxy clustering observations from the Baryon Oscillation Spectroscopic Survey (BOSS), and galaxy-galaxy lensing observations from the overlap between KiDS-1000, BOSS and the spectroscopic 2-degree Field Lensing Survey (2dFLenS). I will summarise the methodology and discuss the cosmological constraints, both within the the standard model of cosmology of a spatially flat Universe filled with cold dark matter and dark energy, and several extensions thereof. These results are then put in the context of the S8 tension: the disagreement between measurements of the cosmic microwave background by Planck and late-time analyses, such as ours, on how strongly matter in the Universe is clustered.

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25/03 - 04:00 pm BRT

David Latham ( Harvard-Smithsonian Center for Astrophysics )

TESS - Transiting Exoplanet Survey Satellite


NASA’s Transiting Exoplanet Survey Satellite finished its primary mission and started its first extended mission on July Fourth, 2020. I will trace the history of the mission and the lessons we learned from Kepler and K2, ending with some of the recent highlights.

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18/03 - 11:00 am BRT

Eduardo Janot Pacheco ( Universidade São Paulo )

The PLATO mission: Brazil chasing exoplanets


PLATO is a medium-class mission of ESA’s Cosmic Vision Program. It will address fundamental questions such as: How do planetary systems form and evolve? Are there other systems with planets like ours, able to develop life? The PLATO instrument consists of 26 small aperture telescopes providing a wide field-of-view and a large photometric magnitude range. It will target bright stars in wide fields to detect and characterize by photometric transit planets in the Habitable Zone down to Earth-size. Asteroseismology will be performed for the host stars to obtain unprecedentedly accurate stellar parameters, including masses and ages. Planet parameters accuracy are intended to be: 2%, 4-10% and 10% for planet radii, masses and ages, respectively. Up to 1,000,000 stars in about 50% of the sky will be observed and hundreds of small planets and thousands of Neptune to gas giants will be characterized, providing the first large-scale catalogue of bulk characterized planets with accurate parameters. The data will allow for the first time robust statistical analysis on physical characteristics of planets, of planetary formation, migration, architecture and evolution and its dependence on spectral type, metallicity and age of the host stars. Thirteen European countries and Brazil are participating in PLATO construction and scientific planning. Brazilian scientists of universities and research centers from all over the country are participating in the preparation of the PLATO mission. We will explore the satellite’s data mainly in the fields of stellar seismology, variable stars, white dwarfs, stellar rotation and exoplanets. Brazilian engineering is developing hardware and software components: a simulator for testing the image reading front-end electronics, photometric masks for imaging extraction, part of the altitude control system and jitter correction. We will give in this talk an overview of the PLATO mission and of the Brazilian participation.

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11/03 - 11:00 am BRT

Sunil Mucesh ( University College London )

A machine learning approach to galaxy properties: Joint redshift-stellar mass PDFs with Random Forest


Point estimates of galaxy properties determined with a small number of photometric bands are imprecise. To fully characterise uncertainties in the estimates, accurate probability distribution functions (PDFs) are required. These PDFs must also reflect the correlations between different quantities of interest. Traditionally, such PDFs are derived by fitting model spectra to photometric data. However, this approach quickly becomes impractical for fitting modern datasets, where sample numbers can exceed hundreds of millions. In this talk, I present a novel method based on the Random Forest (RF) machine-learning (ML) algorithm to generate accurate joint redshift-stellar mass PDFs. I discuss different techniques used to validate both the marginal and joint PDFs. Finally, I demonstrate GALPRO, a Python package capable of producing multivariate PDFs of galaxy properties on-the-fly at incredible speeds, and discuss some of its applications.

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04/03 - 01:00 pm BRT

Leanne Guy ( Vera Rubin Observatory )

Opportunities for Early Science with Rubin/LSST


Starting in 2023, the Vera C. Rubin Observatory will spend its first 10 years conducting the Legacy Survey of Space and Time (LSST). LSST will observe the entire visible southern sky and provide the widest, fastest and deepest view of the night sky ever observed. The resulting astronomical archive will be vast; 500PB of image data products and a 15PB final catalog of ~ 40 billion Objects. LSST will dramatically advance our knowledge in many fields including dark energy and dark matter, as well as galaxy formation and potentially hazardous asteroids. In this talk I give an overview of the Rubin Observatory and the Legacy Survey of Space and Time and talk about opportunities for early science and how to get involved.