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ICCUB PhD projects within INPhINIT, "la Caixa" Foundation Fellowship Programme

Centro/Institution: 
INSTITUT DE CIÈNCIES DEL COSMOS
Tipo/type: 
Predoctoral
País/Country: 
Spain
Fecha inicio solicitud: 
Vie, 16/11/2018
Fecha límite solicitud: 
Mié, 06/02/2019

Descripción/Description: 

The ICCUB is offering 16 PhD projects within INPhINIT program of "la Caixa" Foundation. INPhINIT will select 35 young researchers of all nationalities for a three year program to complete a PhD in one of the centers that has received a distictive Severo Ochoa or Maria de Maeztu award.

Requirements for candidates:

  • In order to be accepted, candidates must meet the following eligibility requirements:
    • Experience: At the call deadline, applicants must be in the first four years (full-time equivalent research experience) of their research careers and not yet have been awarded a doctoral degree.
    • Studies pursued: At the time of recruitment, candidates must comply with one of the following options:

      - To have completed the studies that lead to an official university degree adapted to the European Higher Education Area awarding 300 ECTS credits, of which at least 60 ECTS credits must correspond to master level.

      - To have completed a degree in university not adapted to the European Higher Education Area that gives access to doctoral studies. The verification of an equivalent level of studies to the ones mentioned above will be made by the university when the admission procedure starts.

    • Geographic mobility:
      For candidates applying to Spanish centres or units: Candidates must not have resided or have carried out their main activity (work, studies, etc.) in Spain for more than 12 months in the 3 years immediately prior to the call deadline.

      For candidates applying to Portuguese centres or units: Candidates must not have resided or have carried out their main activity (work, studies, etc.) in Portugal for more than 12 months in the 3 years immediately prior to the call deadline.

      Short stays, such as holidays, done in a country other than their country of usual residence (where they carried out their main activity), will be considered as time spent in their country of usual residence.

    • Level of English: Candidates must have a demonstrable level of English (B2 or higher).
    • Complete applications: Only candidates whose applications meet all the requirements of the call may be accepted.

More information about requirements

The projects offered by ICCUB are:

  • Active Galactic Nuclei in Merging Galaxies: A theoretical Approach[+]

     

    Group Leader: Josep Maria Solanes Majúa
    http://icc.ub.edu/people/68

    Research Project Description

    Supermassive black holes (SMBH) have been detected in the centers of most nearby large galaxies. Galaxies today are not only the products of billions of years of ierarchical structure build up, but also billions of years of SMBH activity as active galactic nuclei (AGN) are thought to be the generic outcome of galaxy-galaxy mergers. In this context, detection of AGN pairs should be relatively common. Observationally, however, dual AGNs are scant, being just a few percent of all AGNs. In this PhD thesis, the candidate will investigate the triggering of AGN activity in merging galaxies via a suite of high-resolution hydrodynamical simulations. (S)He will follow the dynamics of the mergers and trace all processes related to star formation and the accretion of baryons onto the SMBHs, exploring AGN activity across a wide range of relevant conditions and testing when the two AGNs are simultaneously active and for how long. One of the main goals is to derive constraints for the dual AGN fraction detectable through imaging and spectroscopy.

    This thesis is part of a joint research project which involves researchers from the ICCUB and from the Instituto de Astrofísica de Andalucía (IAA) and the Instituto de Astrofísica de Canarias (IAC), both Severo Ochoa Centers of Excellence. This partnership, has been awarded funding by the Spanish Programa Estatal de Fomento de la Investigación Científica y Técnica de Excelencia over the period 2017-19. ICCUB’s contribution to this project mainly lies in using state-of-the-art computer simulations of galaxy interactions and mergers to capture much of the important physics of the processes involved on timescales affordable to study, thus providing a valid reference against which to compare observational data. In short, we are offering the opportunity to participate in a multidisciplinary endeavor that will allow students to acquire advanced academic training in diverse fields, from theoretical astrophysics to high-performance computing.

    Job Position Description

    The PhD candidate should start by familiarizing with the numerical tools and high-resolution collisionless simulations developed by our group, and then contribute to the implementation of the hydrodynamic modeling of the astrophysical dissipative processes related to the gas cooling, star formation, and feedback in galaxies that have a direct bearing on the feeding of their central SMBHs during a merger. (S)He will then perform and analyze a massive suite of numerical simulations of binary galaxy mergers, focusing on the separations and timescales characterizing dual AGN activity. On a later stage, the candidate is also expected to contribute to the extension of the implementation of the evolutionary equations for baryons to forming galaxy groups, in which galaxies experience multiple collisions and mergers with other group companions, as well as strong interactions with the intragroup environment. The goal of this phase would be to build on the knowledge of the formation scenario of first-ranked objects in galaxy aggregations.

    In order to succeed in his/her task, the candidate will have to deal in a totally self-consistent manner with numerical simulations that combine dark, stellar and multiphase gaseous components, and that have a high enough resolution to minimize the effects linked to the two-body heating, angular momentum loses and alterations of the radiative cooling efficiency. In this context, it is worth noting that our group owns a large parallel supercomputer with 40 CPUs and has preferential access to the massive computing infrastructures of the IAA and IAC, where the PhD student will also be expected to carry part of his/her work. This allows us to guarantee that at all times there will be enough computing power available to perform the numerical simulations required by the thesis.

    Individuals with good analytical/research skills and interested in acquiring a high degree of computer literacy are encouraged to apply.

     

  • A numerical and semi-analytical approach to study the radiation from powerful astrophysical outflows[+]
     

    Group Leader: Valentí Bosch-Ramon
    http://icc.ub.edu/people/178

    Research Project Description

    Understanding the astrophysical sources producing ultra-relativistic particles and energetic radiation requires the characterization of the underlying physics, which typically involves complex fluid dynamics, particle acceleration, and radiation processes. This characterization has traditionally relied on models based on strong simplifying assumptions on the emitting region. The recent great improvement in observational instrumentation has slowly pushed the field towards more complex theoretical models, and now it is time to work on fluid dynamics accounting for the production of ultra-relativistic particles and their radiation.

    The project is focused on: (i) getting familiar with semi-analytical modelling of nonthermal emission (ii) working with relativistic magnetohydrodynamical codes to include the presence of very energetic particles and their emission; (iii) application of these tools to powerful galactic and extragalactic sources that feature interaction structures (binary systems, active galactic nucleus jets, etc.) that are expected to strongly radiate gamma rays and lower energy emission; (iv) to compare the accurate computational results with observations of these sources.

    The research group is oriented towards the theoretical modeling of very energetic sources in the Universe. The group leader, Dr. V. Bosch-Ramon, has been working for many years on galactic and extragalactic sources, and has a long experience and knowledge of techniques applied to model these objects. The research group is embedded in a worldly recognized group (part of MAGIC and CTA: VHE instrumentation), led by Prof. J. M. Paredes; the group also hosts other prominent senior scientists, with decades of experience in multi-wavelength observations from radio to gamma rays: the perfect context to plan observations to provide the theoretical research with observational feedback. The research will be carried out in the framework of a powerful international net of collaborators all over the world.

    Job Position Description

    The job position requires some modest experience with structured programming. At least basic understanding of special relativity and fluid dynamics is important. A working knowledge of English is also needed. It is also important to be open to attend conferences and carry out research stays abroad. Finally, what is mostly needed is motivation for solving interesting, but surmountable, physical problems, to work hard, and to learn team work, as well as analytical and synthesis skills.

    There is an important multi-disciplinary element in the job position, as it links basic physics disciplines with applied astrophysics, i.e fluid dynamics in extreme conditions, modeling of radiation from astrophysical sources, and interpretation of observations and planning for prediction testing.

    The doctorate schedule may be organized as follows:

    • The doctoral fellow will develop semi-analytical models and extensions of powerful codes for relativistic magnetohydrodynamics. These extensions will take into account the generation, transport and energy evolution of ultra-relativistic particles in the simulated flow. This tool will permit sound and consistent modeling of powerful and complex sources, not well understood yet. In parallel, the fellow will become familiar with relativistic hydrodynamics, and non-thermal processes. This task would last up to the end of the first half of the PhD.
    • The fellow will apply the developed tools to hot topics in high-energy astrophysics, like gamma-ray production in galactic systems and in extragalactic jets. In parallel, the fellow will become familiar with the observations carried out to study these sources in the whole electromagnetic spectrum. This task would start towards the end of the first year.
    • The fellow may take part in observational campaigns to observe the modeled sources,and participate in the proposal stage as well as in the interpretation of the results.This activity could take place during the second half of the doctoral period.

     

  • Front End electronics for medical imaging and particle detection[+]
     

    Group Leader: David Gascón
    http://icc.ub.edu/people/30

    Research Project Description

    The experimental particle physics (EHEP) research team in the Institute of Cosmos Science in the University of Barcelona (ICCUB) has contributed to heavy flavour experiments during the last 17 years. During this time, the group has developed a significant expertise in the design, manufacturing and operation of custom electronics and microelectronics for the readout of photo-detectors and data processing in other disciplines, such as astrophysics, space or medical imaging.

    The technology developed for the particle physics experiments has been proved to be disruptive for Positron Emission Tomography (PET) in the medical imaging field. Current full-body PET scanners can achieve a 300-ps FWHM Coincidence Time Resolution (CTR) and nowadays the best results found so far could be near 200ps, which can be translated into 3cm spacing resolution. The dream in PET scanners could be to reach the 10ps CTR, i.e., a spatial resolution of 1.5 mm. This 10-fold increase in sensitivity will translate in the reduction of radiation dose, scan time, and cost by an order of magnitude. One way to get closer to the 10-ps CTR is to employ very deep submicron (VDSM) technologies (below 65nm) to develop ultra-fast readout electronics. However, these VDSM processes pose challenges, in particular to the analog front-end (FE) design.

    The main research activities will be:

    • Study different VDSM CMOS technologies and select the most appropriate in terms of performances and cost.
    • Novel topologies for high speed preamplifiers (>1GHz) with ultra-low power consumption (< 200 µW) and very low parallel noise (<< 10 pA/sqrt(Hz)).
    • New architectures for on-chip signal processing: shaping, discrimination, interconnection and parallel processing.

    The benefits of such electronics are not limited to medical imaging. It will open a new era in Light Detection and Ranging (LIDAR) or in particle detectors where precise time detection could be critical in future experiments in the LHC at CERN.

    Job Position Description

    The candidate will join the group as a fellow researcher in the Integrated Circuit (IC) design field. This position will focus on developing a new analog FE architecture to overcome the limitations of the current PET technology. The main objective of this project will be the design of a high-density, low power and large dynamic range Application Specific Integrated Circuit (ASIC) for the readout of photo-sensors, specially, Silicon Photomultipliers (SiPMs). The electronics will be also applied to future high luminosity colliders, where ps time resolution is required for time tagging of particle interactions and also for LIDAR applications.

    She/he will participate in all phases of IC design flow (design, simulation, layout and verification) and characterization of the front-end electronics in lab test benches, particle detectors and hospitals. The candidate will work in a multidisciplinary environment involving also scientists and international researchers. Lastly, the candidate will work in collaboration with other research groups from CERN and from CIEMAT (Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas) and thus learning from high experience engineers.

    The requisites of the candidate are knowledge and experience in:

    • Engineering degree or similar (preferably Electronics Engineer)
    • IC design (schematic, simulation, layout and verification)

    It would also be desirable to have knowledge in:

    • IC testing, PCB design and layout and SW development
    • Data analysis for IC verification and characterization
    • Medical imaging
    • Radiation detectors/li>

     

  • Time to Digital converters for fast readout electronics[+]
     

    Group Leader: Joan Mauricio Ferré
    http://icc.ub.edu/people/326

    Research Project Description

    The experimental particle physics (EHEP) research team in the Universitat de Barcelona has contributed to heavy flavour experiments during the last 17 years. During this time, the group has developed a significant expertise in the design, manufacturing and operation of custom electronics and microelectronics for the readout of photo-detectors and data processing in other disciplines, such as astrophysics, space or medical imaging.

    Positron Emission Tomography (PET) is a diagnosis technique that employs a small quantity of a radioactive substance to obtain molecular images of a living organism by measuring the Time-of-Flight of photons produced by electron-positron annihilation. Commercial full-body PET scanners currently achieve a Coincidence Time Resolution (CTR) of around 300 ps FWHM, i.e., 7.5 cm. Although, there is a lot of effort in decreasing this number, nowadays the best values are around 200 ps, i.e, 3 cm. One of the main challenges in medical imaging is to develop improved readout electronics to get a bit closer to the single photon time stamping at the level of 10ps FWHM, i.e., 1.5 mm intrinsic position uncertainty, which could open the way to paradigm shifts in medical imaging applications.

    A PET system is composed by scintillators, photo-detectors, front-end electronics and back-end electronics to ease the data processing. Front electronics require a fast response to capture precisely the arrival time and energy of the photons generated by a gamma source. The front-end electronics must provide time and energy information into a binary pulse, but this information must still be converted into a digital representation of the time they occurred. Time to Digital Converters (TDCs) are traditionally used for this purpose. In that sense, readout electronics should be designed using very deep submicron (VDSM) technologies (down to 28 nm) to develop ultra-fast TDCs. However, these VDSM processes pose challenges, for instance, in terms of process variations.

    Job Position Description

    The candidate will join the group as a fellow researcher in the Integrated Circuit (IC) design field. This position will focus on developing the back-end electronics, i.e., the TDC, for the electronics of a PET system. The objective is to develop a high density TDCs, including 64 readout channels, with a time stamp with a resolution lower than 10ps and decreasing drastically the power consumption up to 1mW per readout channel. This big decrease in power consumption could be achieve, partially, by employing deep submicron technologies, 65nm and below. The candidate will need to tackle the problems of these technologies, such as process variations which directly translate into performance degradation if the layout is not designed properly. Another challenge will be to integrate the back-end electronics with the front-end electronics into a single chip in to increase the level of integration. Lastly, The TDC could be also applied to future high luminosity colliders, where picosecond time resolution is required for time tagging of particle interactions or other applications such as LIDAR.

    She/he will participate in all phases of IC design flow (design, simulation, layout and verification) and characterization of the modules in lab test benches and particle detectors. The candidate will work in a multidisciplinary environment involving also scientists and international researchers.

    The requisites of the candidate are knowledge and experience in:

    • Engineering degree or similar (preferably Electronics Engineer).
    • IC design (schematic, simulation, layout, verification and physical synthesis).

    It would also be desirable to have knowledge in:

    • IC testing, PCB design and layout and SW development.
    • Data analysis for IC verification and characterization.
    • Medical imaging.

     

  • Exploiting clustering on small (-ish) cosmological scales/PhD Student[+]
     

    Group Leader: Licia Verde
    http://icc.ub.edu/people/99

    Research Project Description

    The Physical Cosmology group (icc.ub.edu/~liciaverde/ICC-Phys.Cosm.html) has been working in Cosmology, connecting theory with observations via interpretation of data since 2007. Our main research interest is making the connection between cosmological observations and the physics behind the standard cosmological model, hoping to shed some light on the “open questions” in cosmology: what is dark matter, what is dark energy? What are the neutrino properties? Is there new physics beyond the standard model for cosmology (which members of the group have actively contributed to establish some 15 years ago or so). Our collective expertise ranges from galaxy evolution to inflation model building but our main strengths are in analysis and interpretation of large-scale structure surveys. Members of the groups are involved in the DESI survey and the Euclid consortium. These are highly international collaborations. In particular the DESI survey is expected to produce data on a timescale shorter than the studentship offering a unique opportunity to exploit these data. We have tight collaborations also with several groups abroad including in Italy, France and UK. In 2018-2019 the group will be composed of two Faculty, one postdoc fellow, three postdocs, and five graduate students, offering a diverse and vibrant learning and research environment.

    Job Position Description

    The current understanding of the Universe is incomplete. According to the standard cosmological model, its dynamics are governed by two components, dark matter and dark energy, for which we only have indirect evidence and fragmentary theoretical comprehension. Unveiling the nature of this dark sector likely requires either a modification in the standard description of fields and particles or an advancement in our understanding of space and time (by modifying Einstein's General Relativity).

    Next-generation galaxy surveys, such as DESI and Euclid, will play a crucial role in disentangling these two competing scenarios. Together with existing low redshift dataset, these new surveys will provide us with an unprecedented amount of 3-dimensional galaxy clustering information and growth of primordial cosmological perturbations under gravity. The combination of these two probes is key in addressing the big open puzzles introduced above.

    Next-generation surveys aim at an order of magnitude improvement on current cosmological constraints coming from these two key measurements, but, for this to be possible, we have to face a number of challenges. Chief among them is modelling non-linearities in an accurate yet fast way. We envision that a combination of analytical and numerical approaches will be needed, in particular on the modelling of the so-called redshift space distortions. A potentially powerful model was originally introduced by members of this group and there is ample room for further developments.

    You will be working with the group on advanced modelling of non-linear scales from both a theoretical and numerical point of view. The results will be a key step in understanding the unprecedented amount of cosmological information that next-generation survey, such as DESI and Euclid, will deliver.

     

  • The blind watchers of the sky[+]
     

    Group Leader: Licia Verde
    http://icc.ub.edu/people/99

    Research Project Description

    The Physical Cosmology group has been working in Cosmology, connectng theory with observatons via interpretaton of data since 2007. Our main research interest is making the connecton between cosmological observatons and the physics behind the standard cosmological model, hoping to shed some light on the “open questons” in cosmology: what is dark mater, what is dark energy? What are the neutrino propertes? Is there new physics beyond the standard model for cosmology (which members of the group have actvely contributed to establish some 15 years ago). Our collectve expertse ranges from galaxy evoluton to infaton model building but our main strengths are in analysis and interpretaton of large-scale structure surveys. Members of the groups are involved in the DESI survey and the Euclid consortum. These are highly internatonal collaboratons. In partcular the DESI survey is expected to produce data on a tmescale shorter than the studentship ofering a unique opportunity to exploit these data. We have tght collaboratons also with several groups abroad including in Italy, France and UK.

    In 2018-2019 the group will be composed of two Faculty, one postdoc fellow, three postdocs, and fve graduate students, ofering a diverse and vibrant learning and research environment.

    Job Position Description

    This project is oriented in develop blinding techniques for the upcoming cosmology surveys, with special emphasis in DESI and Euclid. Since the major science results from these surveys (e.g., determinaton of neutrino masses, informaton on the mass hierarchy, nature of dark mater, nature of dark energy) have profound implicatons for Fundamental physics, beyond cosmology, the same rigorous standards employed e.g. in partcle physics must now also be applied in Cosmology.

    Blinding is a well developed technique in science and in partcular in partcle physics whereby informaton about the test or measurement is masked (kept) from the experimenter, to reduce or eliminate bias, untl afer a trial outcome is known. Its applicaton is wide even beyond physics, for example it is used extensively in medical trials. Blinding has not really been implemented much in cosmology untl very recently and it has not been applied in the analysis of galaxy surveys. But in the era of accurate and precise cosmology it must become a priority for all ongoing and future surveys. Implementng blinding in galaxy surveys analysis opens up a whole new series of challenges which must be addressed to ensure high quality of the scientfc results. Having not only precise and accurate measurements, but also unafected by the prior cosmological analises, is one of the key aspects of to ensure that the fundamental questons that these projects can be answered, and can be directly imported into the other felds they can impact (fundamental physics, partcle physics etc.). You will work with the group and the DESI team on addressing these challenges and on developing and implementng a blinding strategy for DESI. This will be a critcal item in the path to ensure success and recogniton of the experiment.

     

  • Cosmology with massive galaxy large scale structure surveys[+]
     

    Group Leader: Licia Verde
    http://icc.ub.edu/people/99

    Research Project Description

    The Physical Cosmology group has been working in Cosmology, connectng theory with observatons via interpretaton of data since 2007. Our main research interest is making the connecton between cosmological observatons and the physics behind the standard cosmological model, hoping to shed some light on the “open questons” in cosmology: what is dark mater, what is dark energy? What are the neutrino propertes? Is there new physics beyond the standard model for cosmology (which members of the group have actvely contributed to establish some 15 years ago). Our collectve expertse ranges from galaxy evoluton to infaton model building but our main strengths are in analysis and interpretaton of large-scale structure surveys. Members of the groups are involved in the DESI survey and the Euclid consortum. These are highly internatonal collaboratons. In partcular the DESI survey is expected to produce data on a tmescale shorter than the studentship ofering a unique opportunity to exploit these data. We have tght collaboratons also with several groups abroad including in Italy, France and UK.

    In 2018-2019 the group will be composed of two Faculty, one postdoc fellow, three postdocs, and fve graduate students, ofering a diverse and vibrant learning and research environment.

    Job Position Description

    This project aims to study the content of the Universe, its nature and laws through the large scale structure (LSS) of the Universe.

    One of the most outstanding breakthroughs in the recent history of physics has been the discovery of the accelerated expansion of the Universe, initally via observatons of Type Ia SNe, which was awarded with the Nobel Prize of Physics in 2011. Within General Relatvity, such accelerated expansion can only be included through a positve value of the cosmological constant, which counterstrike force of gravity. Such cosmological constant could be understood as the presence of an exotc form of energy associated to the quantum vacuum, which is usually referred as Dark Energy. Within this framework, the current state-of-the-art observatons suggest that only the 4% of the energy-density content of the Universe is made of partcles we understand at fundamental level, whereas the remaining 96% seems to be dominated by exotc forms of mater and energy we are just startng to classify and characterize. What makes up 96% of the Universe? These are the biggest open questons in the feld, and some of the biggest open questons in physics today. In this project you will address such big open questons through the LSS of the Universe, and in partcular with the future massive galaxy surveys, the Dark Energy Spectroscopic Instrument (DESI) and EUCLID. This project focuses on how to maximize the scientfc outcome LSS data that these DESI and EUCLID will deliver. In partcular you will focus on, i) to compress and optmize the amount of informaton that we can extract from observatons or experiments, ii) to use higher order-functons to increase the informaton return from these experiments, iii) to develop new techniques to control and correct the systematcs that otherwise would limit the promised precision of these experiments, vi) to study ways of improving robustness of interpretaton of cosmological results and its wider implicatons.

     

     

  • Fundamental Physics from the Sky[+]
     

    Group Leader: Raul Jimenez
    http://icc.ub.edu/people/98

    Research Project Description

    The Physical Cosmology group (icc.ub.edu/~liciaverde/ICC-Phys.Cosm.html) has been working in Cosmology, connecting theory with observations via interpretation of data since 2007. Our main research interest is making the connection between cosmological observations and the physics behind the standard cosmological model, hoping to shed some light on the “open questions” in cosmology: what is dark matter, what is dark energy? What are the neutrino properties? Is there new physics beyond the standard model for cosmology (which members of the group have actively contributed to establish some 15 years ago or so). Ofur collective expertise ranges from galaxy evolution to inflation model building but our main strengths are in analysis and interpretation of large-scale structure surveys. Members of the groups are involved in the DESI survey and the Euclid consortium. These are highly international collaborations. In particular the DESI survey is expected to produce data on a timescale shorter than the studentship offering a unique opportunity to exploit these data. We have tight collaborations also with several groups abroad including in Italy, France and UK. In 2018-2019 the group will be composed of two Faculty, one postdoc fellow, three postdocs, and five graduate students, offering a diverse and vibrant learning and research environment.

    Job Position Description

    The avalanche of data that current astronomical surveys are bringing, allow for precise exploration of the fundamental laws of physics. What was the origin of the early Universe? How did the Universe evolve to our current state? What is Dark energy? Are there extra-dimensions? Is the Universe homogeneous? What lies beyond the current visible horizon? Many of these questions can be answered by a detailed study of data from the sky and a careful theoretical analysis. This projects lies at the most exciting frontier of knowledge currently: cosmology; it will provide the PhD student with a golden opportunity to exploit the golden trove data that is arriving from telescopes worldwide to unveil fundamental laws of nature. The project aims at using data from current and upcoming cosmological surveys like DESI and EUCLID to explore the above frontier of human knowledge. In particular the student will develop tests and make predictions that can shed light into new physics by exploiting observations of the large scale structure of the sky. In this way, the project will seek to unveil what physics beyond the current LCDM paradigm is there, if any.

     

  • Star formation in the Cosmological Context.[+]
     

    Group Leader:
    http://icc.ub.edu/people/103

    Research Project Description

    Star formation is a crucial process in Cosmology, to understand the re-ionization of the universe and the origin and evolution of galaxies. This PhD project tackle star formation by addressing fundamental questions of its role in the cosmological context: What physical processes control the distribution of stellar masses and the formation rate of stars and how do they change with cosmic time? What was the contribution of the very first stars to the re-ionization of the universe? Do globular clusters probe the early merging activities of mini halos in the standard cold-dark-matter model of the universe?

    The research project consists of developing state-of-the-art computational models, focusing on two key contexts: 1) Magneto-hydrodynamic, cosmological simulations of the first dark-matter halos to collapse and form stars, to study the origin of Population III stars and their possible role in the re-ionization of the universe; 2) Simulations of the collision and merging of mini halos at high redshift, to investigate their possible role in the origin of globular clusters.

    These are challenging multi-scale and multi-physics computational problems, requiring state-of-the-art massively parallel codes and large supercomputing allocations. The development of numerical codes is an important part of this project, which is carried out in close collaboration with the computational astrophysics group at the University of Copenhagen. The group in Barcelona will be composed by Prof. Padoan (group leader), Dr. Frimann, the PhD student, and long-term visitors from the University of Copenhagen. The main collaborators in Copenhagen will be Prof. Nordlund, Prof. Haugbølle. We have a proven track record in the field of computational astrophysics, leading the most challenging supercomputing applications in supersonic turbulence, star formation, solar physics, and plasma physics. We are regularly awarded some of the largest allocations in supercomputing facilities in the USA and Europe.

    Job Position Description

    The PhD student who aspires to lead this project will have a keen interest in fundamental astrophysical processes, a demonstrated aptitude for the development and adoption of numerical codes, and a steadfast determination to become a world leader in the field of star formation, with seminal and transformational contributions.

    Though not a strict prerequisite, expertise in cosmology, hydrodynamics, plasma physics, turbulence theory and interstellar radiative processes is desirable. Good knowledge and experience with programming languages is required.

    The student will lead the development of specific code modules, the set up of numerical simulations and the analysis of their results. She/he will also collaborate in the preparation of supercomputing proposals and will be the leading author of at least two publications per year in the second and third year of the project. The student will attend international conferences, workshops and focused schools on computational methods. She/he will spend part of the time at the Star and Planet Formation Center at the University of Copenhagen, to collaborate in the development of a new hydrodynamic code designed specifically for future exascale supercomputers.

    Because of the multidisciplinary nature of this project, requiring expertise in cosmology, interstellar medium physics, star formation, magneto-hydrodynamics and computational methods, the student is expected to interact with different research groups within the Institute of Cosmos Sciences at the University of Barcelona and at other research centers abroad. Besides the collaborators in Copenhagen, the student will interact with researchers from the University of Helsinki (implementation of radiative transfer codes), Harvard University (physics of turbulence), University of Lund (origin of planetesimals), NASA Ames (modeling of dust evolution), Max Planck Institute of Munich (chemistry of protoplanetary disks).

     

  • The Origin of Terrestrial Planets[+]
     

    Group Leader: Paolo Padoan
    http://icc.ub.edu/people/103

    Research Project Description

    What sets the stage for the formation of rocky planets, possibly hosting conditions favorable to the emergence of life? Planets are the result of the evolution of dusty gaseous disks around young stars born within large clouds of cold interstellar gas containing thousands to millions of solar masses. To model ab initio the formation of protoplanetary disks we must develop a computational framework that captures the complex environment of star forming clouds, including the coupling of turbulence, magnetic fields, stellar radiation and gravity over a vast range of scales.

    The project is composed of two parts: 1) Large-scale simulations of star-forming clouds, to achieve a realistic description of initial and boundary conditions for a large number of young stars and their circumstellar disks. 2) Simulations of dust evolution in protoplanetary disks, embedding billions of inertial particles, to study the transport and evolution of dust grains coupled with the gas dynamics self-consistently.

    These are very challenging multi-scale and multi-physics computational problems, requiring state-of-the-art massively parallel codes and large supercomputing allocations. The development of numerical codes is thus an important part of this project, which is carried out in close collaboration with the computational astrophysics group at the University of Copenhagen. The group in Barcelona will be composed by Prof. Padoan (group leader), Prof. Estalella, Dr. Frimann, the PhD student, and long-term visitors from the University of Copenhagen. The main collaborators in Copenhagen will be Prof. Nordlund, Prof. Haugbølle and Prof. Jørgensen. We have a proven track record in the field of computational astrophysics, leading the most challenging supercomputing applications in supersonic turbulence, star formation, solar physics, and plasma physics.We are regularly awarded some of the largest allocations in supercomputing facilities in the USA (NASA High End Computing) and Europe (PRACE program).

    Job Position Description

    The PhD student who aspires to lead this project will have a keen interest in fundamental astrophysical processes, a demonstrated aptitude for the development and adoption of numerical codes, and a steadfast determination to become a world leader in the field of star formation, with seminal and transformational contributions.

    Though not a strict prerequisite, expertise in cosmology, hydrodynamics, plasma physics, turbulence theory and interstellar radiative processes is desirable. Good knowledge and experience with programming languages is required.

    The student will lead the development of specific code modules, the set up of numerical simulations and the analysis of their results. She/he will also collaborate in the preparation of supercomputing proposals and will be the leading author of at least two publications per year in the second and third year of the project. The student will attend international conferences, workshops and focused schools on computational methods. She/he will spend part of the time at the Star and Planet Formation Center at the University of Copenhagen, to collaborate in the development of a new hydrodynamic code designed specifically for future exascale supercomputers.

    Because of the multidisciplinary nature of this project, requiring expertise in cosmology, interstellar medium physics, star formation, magneto-hydrodynamics and computational methods, the student is expected to interact with different research groups within the Institute of Cosmos Sciences at the University of Barcelona and at other research centers abroad. Besides the collaborators in Copenhagen, the student will interact with researchers from the University of Helsinki (implementation of radiative transfer codes), Harvard University (physics of turbulence), University of Lund (origin of planetesimals), NASA Ames (modeling of dust evolution), Max Planck Institute of Munich (chemistry of protoplanetary disks).

     

  • Astrophysical signatures of wave dark matter[+]
     

    Group Leader: Jordi Miralda-Escudé
    http://icc.ub.edu/people/95

    Research Project Description

    The proposed research focuses on investigating the nature of the dark matter, which comprises about 84% of all the matter in our Universe according to the most recent measurements from the Cosmic Background Radiation fluctuations. Two approaches are proposed for the research: in the first, the consequences of the presence of axions with a mass of the order of ~10(-22)eV as a component of the dark matter will be studied. Axions of this mass should behave as wave systems and would exhibit phenomena that are familiar in atomic physics but on the scale of a galaxy. Specifically, the research may focus on the impact of dynamical relaxation of dark matter in galaxies if all or part of the dark matter is axions of this very low mass. Predictions from this model can be confronted with observations of stellar dynamics in dwarf galaxies, as well as gravitational lensing in clusters of galaxies.

    A second approach would be to study alternative observational techniques through which the nature of the dark matter can be probed, including the possibility of the QCD axion, with a mass or order 10^(-4) eV. An example is the nature of Fast Radio Bursts, which are brief and powerful radio bursts that might be produced by clumps of QCD axion dark matter when colliding with neutron stars. The physics of dynamical relaxation in axion halos mentioned above also has applications to study the density profiles of QCD axion dark matter clumps that are predicted to form from small-scale isocurvature fluctuations in the dark matter density.

    Job Position Description

    The fellow joining this research program would collaborate in all aspects of the research, and would be trained in the required techniques for numerical calculations, cosmological simulation analysis, or observational data analysis that are required. The proposed topic of the nature of the dark matter is fairly broad and the fellow would have freedom to develop the project in the direction that is most promising and appealing. Required skills are a strong background in fundamental physics and mathematics for numerical analysis.

     

  • A multi-messenger view of the extreme Universe: photons, neutrinos and cosmic rays from ative galactic nuclei[+]
     

    Group Leader: Matteo Cerruti
    http://icc.ub.edu/people/68

    Research Project Description

    The origin of the cosmic radiation, a flow of charged particles that constantly hit the Earth, remains, a century after its discovery, one of the major open questions in physics. This is especially the case for the ultra-high-energy cosmic rays (UHECRs), particles with E > 1018 eV. Their origin is likely extragalactic, and their very detection reveals the existence of extremely powerful and efficient cosmic accelerators. Yet, none of them has been clearly identified. With the discovery of active galactic nuclei (AGNs) and quasars at the beginning of the XX century, and the understanding that their extremely high luminosity is due to interaction of matter with a super-massive black-hole, these objects became an obvious candidate to explain UHECRs.

    A powerful tool to investigate the sources of cosmic rays is multi-messenger astronomy: if cosmic rays are accelerated in quasars’ jets, they interact with low-energy photons producing mesons which then decay to photons, leptons and neutrinos. Cosmic ray acceleration is thus inevitably linked to the emission of gamma-rays and neutrinos. On 09/17/2017, IceCube and the gamma-ray instruments Fermi-LAT and MAGIC, observed the first evidence (at the 3 sigma level) of coproduction of photons and neutrinos from an AGN. This event has sparkled interest on AGNs as neutrino emitters, and thus cosmic-ray accelerators. We are currently at a turning point in gamma-ray astronomy: the current generation of Cherenkov telescopes will make way for the new Cherenkov Telescope Array, CTA, which is currently under construction and will be fully operative in the next decade. During the next three years the early CTA data will be available, fostering the first multi-messenger studies in this new era of gamma-ray astronomy.

    The ICCUB is one of the leading laboratories in the Spanish gamma-ray community, with leading roles both in MAGIC and CTA, internationally renowned for its contributions to high-energy astrophysics and gamma-ray astronomy.

    Job Position Description

    The candidate will take an active role in the MAGIC and CTA Collaborations. He/she will have immediate access to MAGIC data, and will perform data analysis on AGNs and IceCube neutrino follow-ups. His/her role in CTA will evolve during the three years of the fellowship, from preparation of the observations and the data analysis, to the analysis of the very first CTA data. As part of his/her duty as collaboration member, the candidate will perform observing shifts at the MAGIC telescopes. Being part of an international collaboration, the position demands high mobility and excellent skills in written and oral communication in English.

    In parallel with the observational efforts, the candidate will work on the theoretical interpretation of the gamma-ray and neutrino data. For this part of the project, he/she will work in close interaction with the high-energy group at ICCUB, developing new numerical codes to simulate hadronic emission mechanisms in extragalactic sources. By comparing the predictions of numerical simulations to the gamma-ray and neutrino data, the candidate will constrain acceleration and radiation mechanisms in AGNs.

    The candidate will present his/her results in international conferences and will take a leading role in writing refereed papers on behalf of the collaborations.

    An excellent background in statistics, data analysis and computational physics is required.

     

  • Data mining of Gaia releases: detection of Ultra Faint Dwarf Galaxies in the Galactic halo as probes for cosmological models[+]
     

    Group Leader: Xavier Luri
    http://icc.ub.edu/people/43

    Research Project Description

    In this project we propose to exploit the Gaia data (ESA, 2 nd Release, 2018 and 3rd Release, 2021) to study a key process that drives the evolution of galaxies: the assemblage of the Galactic halo. The study will be focused on the detection of the “Ultra Faint Dwarf Galaxies” (UFDGs), objects with very low luminosity dominated by dark matter. Very few UFDGs have been discovered in the last decades although its detection is extremely relevant for the so-called “missing satellite problem”, a dramatic discrepancy between the observed number of galaxy satellites and the large number predicted by the state-of-the-art cosmological Λ Cold Dark Matter (CDM) models. Up to now, its detection has been limited to searches of over-densities in specific sky areas and using only photometric surveys. The Gaia catalogue has full sky coverage and, for the first time, extremely accurate stellar kinematics. It opens the possibility to design and apply data mining techniques for searching these structures in an n-dimensional space. Here we aim to obtain a new and unbiased census of UFDGs in the MW.

    To detect UFDGs, the candidate will start by using the Wavelet Transform algorithms already designed by us (Antoja et al., 2015). She/he will use a tessellation method at the Mare Nostrum Supercomputers to run the algorithm using the 2 nd Gaia Data Release (about 1.3x10 9 stars), to derive a first list of new UFDGs we by the end of 2019. Next, new algorithms will be designed, developed and implemented in collaboration with the Workflows and Distributed Computing (WDC) group at the Barcelona Supercomputing Center (BSC). They will be applied both to real Gaia data and to high-resolution hydrodynamic N-body simulations of MW-like galaxies. In collaboration with the UCM (Madrid), and following our previous work (Roca-Fàbrega et al. 2016) we will use simulations obtained by using the newest versions of RAMSES code that include AGN feedback and SMBH formation (resolution lower than 50 pc).

    Job Position Description

    The PhD will be integrated in the Gaia group at the ICCUB under the group leader direction, combined with a co-direction from Dr. Rosa M Badia, leader of the WDC group at the BSC. This dual supervision will ensure the formation and support both in astrophysics and computing sciences. Dr. L.M. Sarro, from UNED, will bring the expertise on Bayesian parametric inference.

    The candidate will participate in the regular Astrophysics, Cosmology training courses (including outreach and communication) at the ICCUB and the BSC. She/he will be responsible to write papers in referred journals. She/he will also join. The WDC group does research in parallel programming models, more specifically in task-based programming models for distributed computing platforms. The group has been deploying their research in the PyCOMPSs/COMPSs programming framework, and has been developing several data mining algorithms like clustering classification and machine learning algorithms.

    The research experience and transferable skills gained will prepare the applicant not only for academy but also, if desired, for a research employment in other fields and even sectors. The applicant will strongly develop problem solving abilities, technical skills on big data, for sure useful in a broader employment market of the current times (e.g. working as a data scientist). We will provide to the candidate the skills needed to deal with the scientific exploitation of Gaia. She/he will be a member of the Gaia GREAT European network, in close connection with the Gaia Challenge DPAC-CU9 Working Group (DPAC: Gaia Data Processing and Analyzing Consortium, 400 European engineers and scientist working in Gaia). That will provide to the candidate training in a number of key areas including galactic and extragalactic astronomy and distributed computing, all of them focused on exploiting advanced database technologies to better facilitate the analysis and interpretation of Gaia's immense datasets.

     

  • Black holes in stellar binary systems[+]
     

    Group Leader: Marc Ribó
    http://icc.ub.edu/people/57

    Research Project Description

    High Mass X-ray Binaries (HMXBs) are binary systems typically composed of a massive B-type star with emission lines (a so-called Be star) and a neutron star (NS). A few years ago, we discovered the first Be star with a black hole (BH) companion, opening a new field of research in HMXBs. We are now studying a second candidate, which, however, has already revealed a different and very interesting behavior, suggesting that it is another type of binary system. Both types of systems are key to understand different evolutionary paths that lead to the formation of BH-NS systems, which are potential sources of gravitational waves when they merge.

    The research project is focused on the discovery and multi-wavelength study of selected HMXBs, with a special emphasis on those containing Be stars with potential BH companions. These sources are potential emitters of gamma rays, as found in the case of the first Be/BH binary system. The project will require inspection and cross-correlation of catalogues, multi-wavelength observations in X-rays and radio, radial velocity studies at optical wavelengths and potential very-high-energy gamma-ray observations above 100 GeV with the MAGIC Cherenkov telescopes. The multi-wavelength observations will be interpreted to extract physical information of the geometries of the binary systems and the particle acceleration and emission/absorption processes taking place within them.

    The research group has worldwide experts in both multi-wavelength observations (Marc Ribó, Josep M. Paredes) and theory (Valentí Bosch-Ramon) of galactic HMXBs. We have a high rate of success in the approval of observational proposals in competitive international observatories with time allocation committees (e.g., Chandra, XMM, VLA, etc.). We are also members of the MAGIC Collaboration and the LST Consortium that operates the first telescope of the Cherenkov Telescope Array (CTA) in La Palma.

    Job Position Description

    This job position is focused on the observational study of binary systems with potential black holes with high-energy emission up to at least X rays. The PhD student will get familiar with HMXBs in general, and with those containing Be stars in particular. He/she will be introduced in the physics of accreting compact objects and in the scenarios producing broadband non-thermal emission. He/she will participate in the scientific justification and technical preparation of observational proposals, as well as in the data reduction and analysis processes, which will conclude in the interpretation of the obtained results and subsequent publication in peer-review international refereed journals. He/she will become member of the MAGIC Collaboration and might have to conduct observational shifts with the MAGIC telescopes.

    During the first year the PhD student will inspect and cross-correlate different multi-wavelength catalogues to search for new black hole candidates in binary systems and will propose observations to identify them. In parallel, he/she will analyze X-ray/radio observations already available and planned for the two Be binary systems identified. He/she will also contribute to understand the observed behavior at other wavelengths.

    During the second year the student will analyze the obtained data from the observations of the black hole candidates proposed in the first year to assess or reject their possible black hole nature. In parallel, he/she will work to build up a physical model that is consistent with the available observational data, to gain knowledge on the physical processes happening inside the already known systems. He/she will also participate in the elaboration of new observational proposals to test the physical models.

    During the third year of the PhD the student will analyze the observations planned during the second year to constrain the physical models of the HMXBs. He/she will summarize the work done to be defended as a PhD Thesis.

     

  • Star formation at high redshift: clues from globular clusters[+]
     

    Group Leader: Mark Gieles
    http://icc.ub.edu/people/543

    Research Project Description

    The stellar initial mass function (IMF) defines how many stars form as a function of their mass. The exact shape, and whether it is universal across space and time, affects a wide range of astrophysical phenomena, from star and galaxy formation to gravitational waves. Evidence for IMF variations was found in elliptical galaxies, based on both stellar kinematics and analyses of their stellar populations. This PhD project will test the “universal IMF hypothesis” by studying the mass function of globular clusters (GCs). These are old, dense stellar systems with a few million stars and were among the first baryonic structures to form in the early Universe. Their stellar populations contain therefore vital information about the IMF at high redshift. In this PhD project, you will develop and use a new method to infer the IMF from GCs. The present day MF of stars and stellar remnants — such as white dwarfs — is modelled by including the effects of dynamical evolution and stellar evolution. The model MF is then used to create dynamical mass models of GCs, which are compared to star count and kinematics from the Hubble Space Telescope (HST) and the ESA--‐Gaia mission. The kinematics of the visible stars is used to constrain the invisible dark stars and stellar remnants! Combining results of GCs with different metallicities, masses and ages enables a unique new test of the universality of the IMF in the earliest phases of galaxy formation. The super--‐visor (Mark Gieles) is an ICREA Research Professor at the ICCUB.

    He is an expert in stellar dynamics, star formation and mass modelling of gravitational systems. He worked as a Royal Society University Research Fellow in the UK (Cambridge and Surrey) and is PI of a European Research Council (ERC) Starting Grant to study dark matter and black holes in the Milky Way. He is part of the “galaxy structure and evolution” group at the ICCUB, which actively participates in the ESA--‐ Gaia mission and related surveys.

    Job Position Description

    We will provide the candidate with the models for the stellar mass function, the dynamical models (LIMEPY) and the methods for fitting the models to the various observations. The supervisor has developed these models and has worked for several years on various observational applications (see related links). There may be the need to do numerical N--‐body simulations on dedicated Graphical Processing Units (GPUs) to generate mock data for doing tests of the dynamical models. Within the ICCUB there is a wealth of experience on scientific exploitation of data from the ESA--‐Gaia mission. This will provide training in a number of key areas on galactic and extragalactic astronomy; all of them focussing on exploiting advanced database technologies to better facilitate the analysis and interpretation of Gaia's immense datasets.

    List of desirable skill sets for the candidates:

    • 1. Basic concepts of stellar and Galactic dynamics;
    • 2. Some experience with statistics: e.g. maximum likelihood methods;
    • 3. Python programming language, Latex editing and Unix/Linux as operating system.

    The candidate will benefit from all the regular Astrophysics, Cosmology and Data Mining training courses at the ICCUB and specific courses on scientific communication and outreach. She/he will be in charge of writing the corresponding papers in refereed journals (Astrophysical Journal, MNRAS, etc). The research experience and transferable skills gained will prepare the applicant not only for academia but also, if desired, for a research employment in other fields and even sectors. The applicant will develop problem--‐solving skills and working with big data, all of which are useful in a broad range of future employments.

     

  • First science with the CTA Large Sized Telescope[+]
     

    Group Leader: Marc Ribó
    http://icc.ub.edu/people/57

    Research Project Description

    During the last 15 years there has been a revolution in our understanding of the Universe at Very High Energy (VHE) gamma rays above 100 GeV. These photons are detected by ground-based Imaging Atmospheric Cherenkov Telescopes (IACTs) like HESS, MAGIC or VERITAS. A population of galactic sources has been unveiled close to the galactic plane, either by deep surveys or by dedicated observations of potential VHE emitters. Some of these sources have been studied in detail with the current generation of IACTs. However, the sensitivity of current experiments prevents the detection of short-term variability in most of these sources and does not allow us to obtain detailed spectra, limiting our understanding of the physical processes responsible of the VHE gamma-ray emission. In addition, a sensitivity improvement would allow us to discover and study in depth new types of sources.

    The Cherenkov Telescope Array (CTA) is the next generation facility for the study of the Universe in VHE gamma rays. It will have a site in the northern hemisphere, located in La Palma (Canary Islands, Spain) and another one in the southern hemisphere, located in Paranal (Chile). The northern site is already being constructed, and the first Large Sized Telescope (LST-1) of CTA has been inaugurated in 2018 October. Commissioning will take place until 2019 October, and first science together with the nearby MAGIC telescopes could be conducted already at the end of 2019. The use of LST-1 together with MAGIC will provide an unprecedented sensitivity at energies around 100 GeV. Since at ICCUB we are both members of the MAGIC Collaboration and the LST Consortium, we will have immediate access to these data. This research project is focused on the first science with the CTA LST and MAGIC, with particular emphasis in the study of transient/variable galactic and extragalactic sources. The research group is led by Dr. M. Ribó (CTA), Dr. J.M. Paredes (MAGIC) and Dr. V. Bosch-Ramon (theory).

    Job Position Description

    This job position is aimed for a young physicist with a strong interest in high-energy astrophysics, with some previous knowledge on the topic. He/she will become a member of the CTA Consortium, the LST sub-consortium and the MAGIC Collaboration. He/she will analyze, for the first time, gamma-ray data of CTA telescopes. For this reason, knowledge in python programming is desirable. The student will work in an international collaboration of hundreds of people and might have to travel de the Canary Island of La Palma to conduct commissioning and/or observational shifts of the LST-1 and MAGIC telescopes.

    During the first year the PhD student will help in the end of the commissioning and in the start of scientific observations with the LST-1 together with the MAGIC telescopes. This will provide him/her with a good knowledge of the data-reduction pipeline, in which development he/she might have to contribute.

    During the second year it is foreseen that the student starts reducing scientific data of galactic and extragalactic transient sources such as microquasars, gamma-ray binaries, gamma-ray bursts or fast radio bursts. The student will participate in the whole process, from the scientific justification of observational proposals to the data reduction, interpretation and publication of the obtained results. There will be particular emphasis in studying detailed VHE spectra to check if they can be fitted with simple power laws or if there are high-energy cut-offs. Short timescale variability will also be studied in these sources. The final goal is to constrain the astrophysical scenarios behind the sources, to unveil if the emission processes are basically leptonic (such as synchrotron and Inverse Compton) or hadronic (pion production and decay).

    During the third year of the PhD the student will propose new observations to be conducted with the 4 LSTs of CTA-North and will summarize the work done to be defended as a PhD Thesis.

     

Applications

All applications must be completed online at:

https://www.lacaixafellowships.org/index.aspx

 

This project has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklowdowska- Curie grant agreement No. 713673