EAS SYMPOSIUM 3: Violent Phenomena in Young Stars

20-22 August 2007

Contact: Tigran Magakian (Armenia)

Explosive events, energetic ejections and extremes in variability characterise the temperamental behaviour of young stars. With the recent expansion in our knowledge through the discovery of gigantic jets on wide degree fields and the detailed features on sub-arcsecond scale, we may now relate cause and effect: the cause of the violent phenomena and the feedback effect on the enveloping cloud.

The recent discoveries of the new examples of extremely rare FU Ori type stars can clarify the role of stellar multiplicity and environment in the jets formation and to make more clear the whole picture of the eruptive phenomena in YSOs. Wide field cameras and near-infrared interferometry stimulated the new searches of HH jets and embedded stars and clusters, which are about to substantially increase our understanding. Modern 3D spectral methods reveal complex inner structures of the jets and give new information about the jet - molecular outflow -ambient medium interaction, opening the possibility to work on more realistic 3D models of jet propagation. High spatial resolution imaging and spectroscopy with space telescopes, as well as ground based interferometry improve our knowledge about launching and collimation mechanisms.

The symposium will provide an ideal platform to see what remains of our old models and bring together new ideas at this critical crossroads. The Byurakan Observatory was one of the locations where the modern ideas concerning early stellar evolution were started to form about 60 years ago; so the JENAM meeting in Armenia is the appropriate place to consider their present development.

SOC

Tigran Magakian (Armenia, Chair), Michael Smith (UK), Bo Reipurth (USA), Sergei Lamzin (Russia), S. Cabrit (France), Tigran Movsessian (Armenia), Francesca Bacciotti (Italy).

Topics:

- Disk accretion and eruptive phenomena
- Disk winds, stellar winds, origin of jets
- Jet excitation, morphology, dynamics and rotation: observations and models
- Molecular jets and outflows
- Evolutional aspects of FUors and EXors. Role of binarity.
- Jet propagation and interaction with ISM
- Dark clouds, globules, nebulous structures around YSO in optics, IR and radio
- Feedback and evolution

Invited talks:

Michael D. Smith (UK): Models of jets origin, propagation and evolution
Catherine Dougados (France): High resolution observations of jets
Chris Davis (UK): Infrared Jets
John Bally (USA): Irradiated jets
Colin Aspin (USA): FUor and EXor Eruptions
Sergej A. Lamzin (Russia): Current models of FUORs
Francesca Bacciotti (Italy): HST observations of jet structure and dynamics
Jose Torrelles (Spain): Masers from outflow sources
Manuel Guedel (Switzerland): X-ray outbursts in young stars
Stephane Guilloteau (France): Millimeter interferometry of outflow sources
Guillem Anglada (Spain): Radio continuum interferometry of outflow regions
Maria Kun (Hungary): YSO clusters and dark clouds
Roland Gredel (Germany): Future observational prospects

Tentative Program:

August 20, Monday

09:00-09:30 Official opening of the JENAM-2007
09:30-10:30 Session 1
10:30-11:00 Coffee break
11:00-12:30 Session 2
12:30-14:00 Lunch
14:00-15:30 Session 3
15:30-16:00 Coffee break
16:00-18:00 Session 4

August 21, Tuesday

09:00-10:30 Plenary sessions
10:30-11:00 Coffee break
11:00-12:30 Session 5
12:30-14:00 Lunch
14:00-15:30 Session 6
15:30-16:00 Coffee break
16:00-18:00 Session 7

August 22, Wednesday

09:00-10:30 Plenary sessions
10:30-11:00 Coffee break
11:00-12:30 Session 8
12:30-14:00 Lunch

- invited talks of 30 minutes, including 5 minutes for questions
- contributed talks of 20 minutes.

This is the preliminary division of the session themes and invited talks.
The talks and speakers who already agreed to participate are marked by (A).
By (S) are marked suggested talks and speakers.

Session 1. Opening. Accretion and eruption processes in YSO
Tigran Magakian (Armenia) 60 years of YSO studies in Byurakan
Jerome Bouvier (France) - CTTS variability and accretion/ejection (A).

Session 2. YSO activity in various wavelengths.
Manuel Guedel (Switzerland): X-ray outbursts in young stars (S)

Session 3. FU Ori and EX Ori type objects.
Colin Aspin (USA): FUor and EXor Eruptions (A).
Sergej A. Lamzin (Russia): Current models of FUORs (A).

Session 4. Physical properties of jets: observations and models
John Bally (USA): Irradiated jets (A).
Johan Eisloeffel (Germany): HST observations of jet structure and dynamics (S)

Session 5. Disk winds, stellar winds and origin of flows
Sylvie Cabrit (France) The origin of jets: observational constraints vs theoretical predictions". (A)
Christian Fendt (Germany): (Theme TBC) (S)

Session 6. YSO population in clouds (?)

Session 7. Jet propagation and interaction with ISM.
Michael D. Smith (UK): Models of jets origin, propagation and evolution (A).
Chris Davis (UK): Infrared Jets (S)

Session 8. Joint discussion and perspectives of further studies.
Roland Gredel (Germany): Future observational prospects (A).