Dr
Gianluigi Bodo
(INAF OATO)
22/05/2018 09:55
We present a numerical study of turbulence and dynamo action in stratified shearing boxes with zero mean magnetic flux. We assume that the fluid obeys the perfect gas law and has finite (constant) thermal diffusivity. We identify two regimes. The first is a conductive regime in which the heat is transported mostly by conduction and the density decreases with height. In the limit of large...
Prof.
Nektarios Vlahakis
(Department of Physics, University of Athens, Greece)
22/05/2018 10:25
The linear stability of magnetized jets against nonaxisymmetric modes will be discussed.
Prof.
KANARIS TSINGANOS
(UNIVERSITY OF ATHENS)
22/05/2018 11:15
A criterion is derived for distinguishing if a rotating hydrodynamic outflow emerging from the atmosphere and the gravitational well of a central object obtains a radial (wind) or cylindrical (jet) asymptotical shape. Quasi-analytical solutions are obtained via a nonlinear separation of the variables, which are the spherical distance and the mass flux function, in the relevant physical...
Prof.
Turlough Downes
(Centre for Astrophysics and Relativity, Dublin City University)
22/05/2018 12:15
Diffusion of, and turbulence in, magnetic fields are believed to be critical to various processes in astrophysics such as particle acceleration, magnetic reconnection and star formation. It has been suggested that MHD turbulence itself can play a critical role in magnetic field diffusion. If this is true then it implies that some of our notions about global structures in turbulent...
Mme
catherine dougados
(ipag)
22/05/2018 14:00
Powerful atomic jets and molecular outflows are observed in young protostars at all stages of active accretion, from the young embedded Class 0 and Class 1 phases to the later optically revealed T Tauri or Class 2 phase. The origin of the ejection, its role in angular momentum extraction and impact on protoplanetary disk evolution remain as fundamental open questions in star formation.
...
Brunella Nisini
(INAF Osservatorio di Roma)
22/05/2018 14:30
I will present a survey of forbidden line emission in a sample of 130 T Tauri stars in the Lupus, Chamaeleon and sigma Ori clouds conducted with the X-shooter instrument. The aim of the survey is to study the occurrence of high velocity jets and slow winds on a statistical bases, and investigate on the connection between the different mass loss phenomena and the source accretion properties.
Dr
Dirk Froebrich
(University of Kent)
22/05/2018 15:00
The talk will present the main results from the UK Wide-field Infrared survey for H2 (UWISH2).
Mme
Fatima Lopez-Martinez
(Instituto de Astrofísica e Ciências do Espaço)
22/05/2018 15:30
Winds and jets are key factors in the evolution of accretion disks in pre-main sequence stars, and deriving their physical properties is one of the most important steps for a full understanding of the connection among outflow, jet and accretion processes. In this work we determine the physical properties of the high velocity component (HVC) and the low velocity component (LVC) emitting region...
Prof.
Tom Ray
(Dublin Institute for Advanced Studies)
22/05/2018 16:30
The European Commission has made a large number of changes to the structure of innovative training networks (ITNs) in comparison to "The JETSET Era". Here I will look at these changes, explain the level of funding one might expect and what the budget will cover. I will also outline the differences, not always obvious, between the 3 main selection criteria of Excellence, Impact and...
Dr
Ovidiu Tesileanu
(ELI-NP, IFIN-HH, Romania)
23/05/2018 09:45
Extreme Light Infrastructure – Nuclear Physics (ELI-NP) is the Romanian pillar of the pan-European distributed research facility based on ultra-short-pulse lasers. Due to the unprecedented intensity regimes the 10PW lasers at ELI-NP can reach, and also to the combination of beams that can be synchronized and made available at the same time, new experiments relevant for the extreme conditions...
Jochen Eislöffel
(Thüringer Landessternwarte)
23/05/2018 10:45
We will present new observations from accretion bursts from young stars.
Dr
Aris Tritsis
(Research School of Astronomy and Astrophysics)
23/05/2018 11:45
Molecular clouds are the birthplaces of stars. Their structure and evolution hold the key to understanding the initial conditions of star and planet formation, and the physics that sets the distribution of masses and multiplicities of newborn stars. However, their complexity, their typically turbulent, filamentary, disordered appearance, and ubiquitous projection effects hinder all efforts to...
Christian Fendt
(Max Planck Institute for Astronomy)
23/05/2018 14:00
I will present results of recent jet launching MHD simulations. These include simulations considering a dynamo-generated disk magnetic flux, and simulations in 3D thus considering jet launching in binary systems. I will also discuss a general interrelation between the disk magnetization and the jet dynamical parameters.
Lionel de Sa
(LERMA, Sorbonne Université, Observatoire de Paris, Université PSL, CNRS, Paris, France & CEA/DSM/IRFU/SAp-AIM, CEA Saclay, CNRS, Gif-sur-Yvette, France)
23/05/2018 14:30
Many questions still remain open on the stellar accretion process which occurs during the first phases of the life of young stars and consequently the details in the exchange of mass and momentum between the proto-star and its accretion disk still remain approximate: the topology of the accretion flow, its temperature, its observability in the UV and X-ray bands, the possibility of any...
M.
Salvatore Colombo
(Università di Palermo, Pierre et Marie Curie University, INAF - Istituto Nazionale di Astrofisica)
23/05/2018 15:00
CTTSs are young stars accreting mass from their circumstellar disks. According to the largely accepted magnetospheric accretion scenario, the disk extends until the truncation radius, where the magnetic field is strong enough to disrupt the disk and to channel the material towards the star forming an accretion column. The material falls into the star at free fall velocity and hits the stellar...
Dr
Francesca Bacciotti
(INAF - Osservatorio Astrofisico di Arcetri)
24/05/2018 10:00
We have recently obtained ALMA Band 7 polarimetric data for the young systems DG Tau and CW Tau,
for which the rotation properties of jet and disk have been investigated in previous high angular resolution studies.
The motivation was to test the models of magneto-centrifugal launch of jets via the determination of the magnetic configuration at the disk surface. Non-spherical dust grains...
Mlle
Sabina Ustamujic
(Universidad Complutense de Madrid)
24/05/2018 10:30
Observations of stellar jets show evidence of X-ray emitting shocks close to the launching site. In some cases, including YSOs at different stages of evolution, the shocked features appear to be stationary (e.g. HH 154 and DG Tau). We study the case of HH 154, the jet originating from the embedded binary Class 0/I protostar IRS 5, and the case of the jet associated with DG Tau, a more evolved...
M.
Dimitrios Millas
(KU LEUVEN)
24/05/2018 11:30
Supernovae (SN) and astrophysical jets are two of the most energetic and intriguing objects in the universe. We examine an interesting scenario that involves the interaction of these two extreme phenomena, uniquely ''combined'' in the W50-SS433 system: a jet launched from the microquasar SS433 (an X-ray binary, XRB) located inside a supernova remnant (SNR), W50. Observations have revealed a...
Dr
ZAKARIA MELIANI
(LUTH, Observatoire de Paris)
24/05/2018 12:00
We investigate the plasmoid knot formation in stratified relativistic jet by means of relativistic magneto-hydrodynamics simulations. Indeed, astrophysical jets in active galactic nuclei seem to be transversely stratified, with a fast inner jet and a slower outer jet. As it is likely that the launching mechanism for each component is different. In the other hand, the steady and moving knots...
Claudio Zanni
(INAF - Osservatorio Astrofisico di Torino)
24/05/2018 12:30
The spin evolution of classical TTauri stars (CTTS) represents a puzzling problem. Since they are still contracting and accreting, these protostars would be expected to spin-up at breakup speed in a few million years. On the other hand, as soon as they emerge from the Class 0-I embedded phases, they are observed to rotate with periods between 1-10 days, well below their breakup limit. In...
Rosaria Bonito
(INAF - Osservatorio Astronomico di Palermo)
24/05/2018 14:00
High energy emission from young stars with disks, with all their components due to accretion and outflow activity, can have a deep impact on the evolution of their disks and on the formation of exo-planetary systems.
An inter-disciplinary approach, which combines multi-wavelength observations, magnetohydrodynamical models, and laboratory experiments, allows us to get a more complete...
Dr
Salvatore Orlando
(INAF-Osservatorio Astronomico di Palermo)
24/05/2018 14:30
Accretion of matter is a process that plays a central role in the physics of young stellar objects. The analysis of the structure by which matter settles on the star can unveil key information about the process of star formation by providing details on mass accretion rates, stellar magnetic field configurations, possible effects of accretion on the stellar coronal activity, etc.
Here we...
Dr
Fabrizio Massi
(INAF-Osservatorio Astrofisico di Arcetri)
24/05/2018 15:00
In this talk I will present the first results of our GIARPS survey of a sample of T-Tauri and Herbig AeBe stars ($\sim 100$ objects), belonging to the GRAVITY/VLTI GTO sample of Young
Stellar Objects (YSOs).
GIARPS is a broad-band spectrometer combining HARPS-N and GIANO which allows obtaining high-resolution spectra from 0.44 micron (R $\sim 115000$) to 2.44 micron (R $\sim$ 50000) in one...
Dr
Odysseas Dionatos
(University of Vienna)
24/05/2018 15:30
The conclusion of JETSET roughly coincided with the beginning of a new era when facilities such as Herschel and ALMA became operative, opening new observational possibilities in terms of sensitivity, angular and spectral resolutions. In this talk I will report on my continuing efforts to understand the role of jets and outflows in connection to their driving sources but also with respect to...
Prof.
Ana Gomez de Castro
(Universidad Complutense)
In this talk, we'll address the impact of UV radiation from the jet on the evolution of protoplanetary and young planetary disks
