Seminar about “The High Energy Universe: Ultra High Energy Cosmic Rays, Active Galactic Nuclei and Gamma-ray Bursts”

Hercules A (an active galactic nucleus). Visible light image obtained by Hubble Telescope superposed with a radio image taken by the Very Large Array (VLA)

Guest: Dr. Athina Meli, Liège University, Belgium and Athens Institute for Education and Research, Greece

When: 23 May 2018, from 11:00

Where: ISS, Auditorium

Abstract:

The Universe is filled with a rich diversity of high-energy phenomena and highly energetic processes. Great developments in astrophysical observations over the last years, as well as in-tandem simulation studies, opened a wide window into the understanding of the electromagnetic wavebands of astrophysical phenomena, from the radio waves up to the high-energy gamma-rays but also to high energy cosmic-rays, which carry a multitude of information about the most energetic phenomena in Cosmos. Accelerated particles (cosmic-rays) are believed to be created in the cataclysmic ”explosions” of astrophysical sources like Gamma-Ray-Bursts and in the jets of Active Galactic Nuclei. The acceleration of cosmic-rays and the emission of very high energy electromagnetic radiation (i.e., x-rays, gamma-rays) mostly occur in the relativistic superalfvenic cosmic plasmas and jets that act as cosmic accelerators. In this talk I will give an overview of these high-energy accelerators and will discuss the mechanisms responsible to producing very high-energy cosmic rays and radiation.

Contact person: Dr. Ioana Dutan <idutan[at]spacescience[dot]ro>

 

Intensive Course about: Computational Methods for Kinetic Processes in Plasma Physics

Particle-in-cell numerical simulations for an electron-proton plasma jet with a larger radius. Credit: Nishikawa et al., Galaxies, 5(4), 58, 2017.

Instructor: Dr. Ken-Ichi Nishikawa, University of Alabama, Huntsville, SUA

When: 21-25 May 2018. Course hours:

Mo: 2pm-4pm;
 Tu: 10am-12am and 2pm-4pm; Wed: 2pm-4pm;
 Thu: 10am-12am and 2pm-4pm; Fri: 10am-12am

Where: ISS, Auditorium

Abstract:

This course is intended to provide students/researchers with basic concepts of computer simulations using a particle-in-cell (PIC) numerical code in order to understand kinetic processes in plasmas. PIC simulation is, in principle, an accurate method and provides the widest range of plasma effects. Nowadays, the computer power is powerful enough to perform reasonable 3-dimensional (3D) simulations to investigate realistic plasma dynamics. The course will cover the fundamental concepts of plasma simulation by performing small 3D electromagnetic codes with applications to relativistic jets. Starting with a brief introduction to plasma physics, the mathematics and physics behind the algorithms will be described. We will explore how PIC simulations reveal plasma behaviors as they are highly nonlinear phenomena. Some examples of how to run the PIC simulations will be also given.

Overview:

  1. Plasma physics on computer (general description)
  2. Kinetic plasma simulations (nonphysical instability, approximate nonlinear analysis, plasma behavior, linear weighting, nonphysical effects)
  3. How PIC works (cold plasma dispersion, plasma dispersion function)
  4. Electrostatic codes (grid quantities, beat heating)
  5. Electromagnetic codes (hybrid oscillation, warm and unmagnetized plasmas)
  6. Finite-difference time-domain Maxwell solver on Yee grid: leapfrog algorithm
  7. Particle movers: Boris’s algorithm
  8. Conservative charge deposition method
  9. Boundary conditions (particles and fields)
  10. Simulations for astrophysical plasmas
  11. Recent work: (1) Weibel instability in relativistic jets (radiation, weighted beam) and (2) Reconnection (particle acceleration)

Reference: “Plasma Physics via Computer Simulation (Series in Plasma Physics)”, C.K. Birdsall & A.B. Langdon; Programs in the text book are written in Fortran.

Prerequisites: Elementary physics (Bachelor level)

Registration: Subscription for attending the course should be sent to Dr. Ioana Dutan <idutan[at]spacescience[dot]ro>, with your name, status (e.g., student, researcher) and affiliation, no later than May 15th 2018.

The event can be followed live on the ISS Facebook and YouTube channels.

List of participants

Photo Gallery:

Seminar about: Reconnection and associated flares in global relativistic jets containing helical magnetic fields with particle-in-cell simulations

Dr. Ken-Ichi Nishikawa, University of Alabama in Huntsville, USA

Guest: Dr. Ken-Ichi Nishikawa, University of Alabama in Huntsville, USA

When: 21th May 2018, from 11:00

Where: Institute of Space Science – ISS (Auditorium)

Abstract:

The discovery by Advanced LIGO/Virgo of gravitational waves from the binary neutron star (BNS) merger GW170817 triggered sequential observations of the electromagnetic counterparts, which has opened the era of multi-messenger astronomy. These multi-frequency observations provide us profound information to investigate the processes from the generation of gravitational wave, associated relativistic jets and merger ejecta, and consequently radiation from the interaction of jets and ejecta with interstellar medium. The investigation of these phenomena requires extensive and systematic theoretical and computational research with various observations. In the study of relativistic jets one of the key open questions is their interaction with the environment on the microscopic level. We have studied the initial evolution of both electron–proton and electron–positron relativistic jets containing helical magnetic fields, focusing on their interaction with an ambient plasma. We have performed particle-in-cell simulations of “global” jets containing helical magnetic fields in order to examine how helical magnetic fields affect kinetic instabilities such as the Weibel instability, the kinetic Kelvin-Helmholtz instability (kKHI) and the Mushroom instability (MI) using a larger jet radius. In our previous simulation study, these kinetic instabilities are suppressed and new types of instabilities can grow. In the electron-proton jet simulation a recollimation-like instability occurs near the center of jet. In the electron-positron jet simulation mixed kinetic instabilities grow and the jet electrons are accelerated. In this talk, I will present results of synthetic radiation spectra that are obtained directly from simulations using much larger systems for global jets containing helical magnetic fields., which can then be compared with observations of gamma-ray burst objects. I will also present possible mechanisms of X-ray flare production for such objects due to magnetic reconnection.

Contact person: Dr. Ioana Dutan <idutan[at]spacescience[dot]ro>

 

Conference about “Societal changes determined by the national program of JAXA Space Education Center”

Organizers: ISS and the White Cross Foundation

Guests:

When: 6th March 2018, from 09:00

Where: Institute of Space Science – ISS (Auditorium)

Abstract:

The speakers, experts of JAXA (Japan Aerospace Exploration Agency), will present the premises, methods used and the national program results of promoting curiosity and the adventure spirit, as well as creativity, applied to children with the purpose of generating not only further generations of researchers in aerospace sciences but moreover citizens with broad vision and respect for scientific research.

Access to the conference <see program > will be made exclusively upon registration here.

The event can be followed live on the ISS Facebook and YouTube channels.

Contact person: Cristian Dumitru Ionescu <idcristi[at]spacescience[do]ro>

 

Participation of the Institute of Space Science to LISA space mission

Illustration of a LISA mission satellite. © AEI/MM/exozet; GW simulation: NASA/C. Henze

The Institute of Space Science was represented at the LISA Consortium Meeting – LISA Phase A Activities, which took place between January 29th – 30th, 2018, at the Max-Planck Institute for Gravitational Physics (Albert Einstein Institute), in Hannover, Germany, by Dr. Ion Sorin ZGURĂ, Director of the Institute of Space Science, Dr. Laurențiu Ioan CARAMETE, Head of the Cosmology and AstroParticle Physics Group and Dr. Eugeniu Mihnea Popescu, Head of the High Energy Astrophysics and Advanced Technology Group. The status of the future LISA space mission, which is an L-type (Large) mission of the European Space Agency, was presented, as well as the foreseen contributions of each entity in the consortium.

The Laser Interferometer Space Antenna (LISA) will be the first space-based gravitational wave observatory and it will consist of 3 satellites joined by laser interferometers, placed in a triangle, at a distance of 2.5 million kilometers that will follow the Earth in its orbit around the Sun for an in-depth study of the Gravitational Universe. The satellites will have similar characteristics with the LISA Pathfinder mission, which flew successfully in December 2015 and has tested the most important technical components.

The Institute of Space Science will contribute to the LISA space mission with the Constellation Acquisition Sensor (CAS) system, which will verify the alignment of the 3 satellites, ensuring the acquisition of the laser signal on the interferometric detectors. Together with the Coarse Star Tracker (STR) system, CAS will check the visualization of the laser signal at the scanning maneuver stage. This contribution is fully supported by the Romanian Space Agency (by the programs “Romanian Incentive Scheme”, PRODEX and national programs) and is in excellent agreement with the Institute of Space Science strategy, as well as with the national strategy of research and development in Romania.

At the express request of the LISA Consortium, the Romanian Space Agency (ROSA) appointed as representative in the “LISA National Agency Board” (which has representatives from each national space agency in the consortium) Dr. Marius-Ioan Piso, president and CEO of the Romanian Space Agency, who is recognized by the scientific community as one of the main initiators of gravitational radiation research since the ’80s. Also, Dr. Ion Sorin ZGURĂ, Director of the Institute of Space Science was appointed as delegate member in the LISA National Agency Board.

LISA space mission is proposed by an international consortium made by researchers from Germany, Italy, Switzerland, United Kingdom, Spain, Denmark, Holland, Romania, Belgium, Portugal, Sweden, Hungary and United States of America. The launch of LISA is foreseen in 2034, with a lifetime of the mission for 4 years and the possibility of an extension up to 10 years.

Contact person: Dr. Laurențiu Ioan CARAMETE <lcaramete[at]spacescience[dot]ro>

Photo gallery

 

Dr. Laurențiu Ioan Caramete (left) and Dr. Ion Sorin Zgură (right) at the LISA Consortium Meeting – LISA Phase A Activities
Presentation of the Institute of Space Science contribution, at the LISA Consortium Meeting – LISA Phase A Activities, given by Dr. Laurențiu Ioan Caramete

 

Seminar about “Euclid Science Ground Segment, how to obtain Science from raw Space Telemetry”

Artist’s impression of the Euclid spacecraft. Credit: ESA/C. Carreau

Guest: Dr. Andrea Zacchei, Astronomical Observatory of Trieste

When: November 22th, 2017, 11h00

Where: Institute of Space Science – ISS (Auditorium)

Abstract:

The organization, development and operation of a Science Ground Segment for a Space Mission is a very complex system. Its costs are at the level of an instrument development with the additional complexity of a NOT centralized system. Strategy used in the creation of the Euclid Ground Segment will be discussed with emphasis on the technical solution adopted.

Contact person: Dr. Lucia A. Popa (ISS) <lpopa[at]spacescience[dot]ro>

Seminar on “History of the Romanian space magnetometers”

Organizer: ISS, The Space Plasma and Magnetometry Laboratory – 1040

Speakers: Dr. Mircea Ciobanu (ISS) and Dr. Marin Sâmpăleanu (University of Calgary, Canada)

When: 14 June 2017, at 11:00

Where: Institute of Space Science – ISS (Auditorium)

Abstract:

The space magnetometers designed and released at the Platform of Physics in Magurele, Romania, has become the most required instruments for measuring the Earth’s magnetic field in frame of the INTERCOSMOS Program, in period 1978-1990. The essential elements that have made possible this success would be presented.

The seminar is open to the public and it can be followed live on the ISS Facebook and YouTube channel.

Contact person: Cătălin Negrea <negreacatalin [at] spacescience [dot] ro>

Seminar on “High-Energy Cosmic Ray Acceleration in Relativistic Jets”

Artistic impression of a super-massive black hole with relativistic jets. Credit: ESA/NASA/AVO/Padovani

Guest: Dr. Athina Meli, Department of Physics and Astronomy, University of Gent, Belgium

When: Wednesday, March 22nd, 2017, from 11h00

Where: Institute of Space Science (Auditorium)

Abstract:

The Fermi acceleration mechanism at shocks is invoked to explain non-thermal cosmic-rays in Supernova Remnants, Active Galactic Nuclei Jets and Gamma ray Bursts. The importance of achieving the highest observed cosmic-ray energies by such a mechanism in extragalactic astrophysical environments is a recurring theme. Moreover, relativistic shocks, either single or multiple, have been inferred by observations to be forming within a high-speed plasma jet in extragalactic, relativistic sources. The acceleration of cosmic-rays via the Fermi acceleration mechanism in these shocks is believed to be responsible for the observed cosmic-ray power-law distributions and consequently for the radiation of gamma-rays and neutrinos. In this talk, I will focus on the relativistic cosmic-ray shock acceleration mechanism by giving an overview, will present Monte Carlo test-particle simulation studies for relativistic single and multiple shocks, and will briefly discuss the secondary production and extragalactic propagation of the accelerated high-energy cosmic-rays, giving some insights of their relevance to a multi-messenger physics approach.

Contact person: Ioana Duțan <idutan [at] spacescience [dot] ro>

 

NASA reveals the existence of an exoplanetary system at 40 light years away from Earth

Artistic Illustration of the TRAPPIST-1 system. Source NASA.

On February 22nd, 2017, through a press release, NASA reveals a historic discovery concerning the existence of new exoplanetary system, called TRAPPIST-1, which hosts seven planets, comparable in size and mass with Earth; three of them being located in the habitable zone, the most likely to have liquid water. The super-cool dwarf star, located at about 40 light years away from Earth, is being named after the TRAPPIST mission – Transiting Planets and Planetesimals Small Telescopes.

”One light year means about nine trillion kilometers, i.e at one milliard add three more zeroes. At the moment we cannot perceive yet to cover such a distance with human capabilities. Perhaps, it is necessary a paradigm shift, a change of perception, which will allow us, hopefully in a near future, to see how we could access these stars”, says President of the Romanian Space Agency (ROSA), Dr. Marius-Ioan Piso, in an interview accorded at Radio France International (RFI).

The observations began at the end of 2015, when a team of astronomers from University of Liege, Belgium, decoded the data acquired with the Liege telescope TRAPPIST-Sud, located in Chile. Further ongoing observations have implied more telescopes on-ground (TRAPPIST-Nord in Morocco, UK Infrared Telescope – UKIRT in Hawaii, William Herschel and Liverpool telescopes in La Palma, and the South African Astronomical Observatory telescope) and the NASA’s Spitzer space telescope.

In order to detail the atmospheric composition, or the structure of the rock of those planets, we may need perhaps a decade from now on”, says scientific researcher at the Institute of Space Science (ISS), Dr. Gina Isar, in an interview accorded at Antena 1 Observator TV.

However, NASA has made the reveal that seven planets revolve around TRAPPIST-1, through long and dedicated observations of better precision with the Spitzer space telescope. The remarkable results were recently published in Nature, which conclude that: “The TRAPPIST-1 system represents a unique opportunity to thoroughly characterize temperature Earth-like planets that are orbiting a much cooler and smaller star than the Sun” [Gillon, M. et al. Nature, 2017].

The TRAPPIST telescopes are part of a wider project called SPECULOOS – Search for habitable Planets EClipsing Ultra-cOOl Stars, which aims to detect more systems of this type, with four new telescopes in Chile.

Further observations will continue with new performant telescopes, both on ground and in space.

More information on the TRAPPIST telescopes can be found here.

More information on the SPECULOOS project can be found here.

 

INA – An interactive software tool for the statistical analysis of time series with application to space plasma turbulence

ina_diagram
The diagram of INA and the schematic illustration of its main functionalities.

INA (Integrated Nonlinear Analysis) is an interactive software product designed to analyze satellite data with advanced nonlinear methods adapted to space plasma turbulence research. The software is developed in the framework of the European Community’s Seventh Framework Programme project STORM (Solar system plasma Turbulence: Observations, inteRmittency and Multifractals) where ISS had a significant contribution. The main developers are Dr. Costel Munteanu (scientist at the Institute of Space Science – ISS), Dr. Marius Echim (senior scientist at ISS and also at the Belgian Institute for Space Aeronomy (BISA), Brussels) and Dr. Peter Kovacs (senior scientist at the Geological and Geophysical Institute of Hungary, Budapest).

INA is publicly available from the website of the project (http://www.storm-fp7.eu) as an executable file to be run under Windows or Linux operating systems. The download page is available after registration by email to marius.echim@oma.be.

The software is written in MATLAB (version 2015a), but it can also be used independently by installing a MATLAB compiler, which can be downloaded freely from here. Through an intuitive graphical user interface (GUI), INA provides a complete statistical analysis of a time series and provides various methods: descriptive analysis, power spectral density (PSD), spectrogram analysis, analysis of probability distribution functions (PDF) of fluctuations, wavelet analysis, structure function analysis (SF), and multifractal analysis using the rank ordered multifractal analysis (ROMA).

INA is optimized for the analysis of magnetic field and plasma data provided by Venus Express, Cluster and Ulysses satellites, but has also adequate modules for reading and analyzing other data types.

For more information about INA, the software developers can be contacted directly by email: Dr. Marius Echim <marius.echim [at] oma [dot] be>, Dr. Costel Munteanu <costelm [at] spacescience [dot] ro>, Dr. Peter Kovacs <kovacs [dot] peter [at] mfgi [dot] hu>.

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