Investigating the origin of stellar jets with SPHERE

Transcription

1 Investigating the origin of stellar jets with SPHERE HH 30 - HST Linda Podio (INAF-Arcetri) & Simone Antoniucci (INAF-Rome) SPHERE Consortium SVT proposal (1 target): Dec P94 EGTO-Other Science (2 targets): Jan 1-8, Mar P95 GTO-Other Science (1 target): April TEAM: F. Bacciotti (INAF-Arcetri), B. Nisini, T. Giannini (INAF-Rome), R. Gratton, M. Turatto, S. Desidera (INAF-Padova), E. Lagadec (Cote d Azur, PI GTO-Other Science), G. Chauvin, M. Benisty, M. Bonnefoy (IPAG-Grenoble)

2 JETS & DISKS are tightly connected MHD models: the jet is launched & accelerated by magneto-centrifugal forces Jets may remove angular momentum from the disk DISK WIND Konigl & Pudritz 2007 STELLAR WIND Sauty et al AU < 0.1 AU X-WIND Shu et al. 1994, 2000 OPEN QUESTIONS: What is the jet launching mechanism? What is the jet feedback on the disk in the region of planet formation?

3 Jet dynamical feedback on the protoplanetary disk Effects of jet magnetic torque on the disk: - angular momentum removal - density structure of the disk - pressure bumps - migration Zanni & Ferreira 2013 Jet asymmetry: - same mass loss rate Ṁ jet ~ n H *V jet - different momentum Ṗ jet ~ Ṁ jet *V jet does it affects the disk? e.g., inclined and eccentric orbits HH 34 - VLT DG Tau B - Keck Podio et al. 2011

4 Jet irradiation feedback on the protoplanetary disk DG Tau: bipolar X-ray jet - CHANDRA X-ray/UV from jet shocks: irradiation of disk surface? Gudel et al Podio et al. 2006, 2009 Panoglou et al Shielding by dusty winds : does it affects photoevaporation and disk clearing?

5 High Angular Resolution Observations of Jets narrow-band imaging HH 30 with HST 0.1 Ray et al 1996, Bacciotti et al AO imaging [S II] 6731 A DG TAU with CFHT 0.1 Dougados et al long-slit spectrum [S II] 6731 A DG TAU with STIS/HST R=6000 Maurri et al IFU image [Fe II] + H2 DG TAU with SINFONI R=3000 Agra-Amboage et al. 2014

6 High Angular Resolution Observations of Jets narrow-band imaging HH 30 with HST 0.1 Ray et al 1996, Bacciotti et al DG TAU with CFHT Limits of previous high AO imaging angular resolution observations: 0.1 [S II] 6731 A Dougados et al ) resolution 0.1 2) poor contrast for bright sources, e.g. Herbigs DG TAU with STIS/HST 3) coronagraph 0.3 long-slit spectrum R=6000 [S II] 6731 A Maurri et al IFU image [Fe II] + H2 DG TAU with SINFONI R=3000 Agra-Amboage et al. 2014

7 Observing with SPHERE Goal: understand HOW the jet is launched (in particular for Herbigs) understand IF and HOW the jet affects the disk structure Need: to image the jet down to a few AUs from the source > high spatial resolution (< 0.1 ), high contrast ( ) images HST 0.6um images DL Tau jet HST coronagraph: stop radius (> 300 mas) too large to probe the innermost regions of disks and jets Grady et al. 2004

8 Observing with SPHERE JET PROPERTIES Emission lines VIS - NIR Source = guide star Nearby systems (d~100 pc) Contrast 10^3-10^5 Associated to disks Interesting FOV 1. 5 x 1. 5 ZIMPOL (optical) NB imaging + coronagraph [O I], Hα + adjacent cont IRDIS (NIR) NB imaging + coronagraph [Fe II], H2, Paβ, Brγ + adjacent cont IFS (NIR) NIR lines & adj cont simultaneously low spectral resolution = NB imaging coronagraph? EXP TIME: 1 hours per target/line

9 Target for SVT & EGTO-P94: The twin jets from ZCma Z CMa jet Z CMa: , Nov-Mar V = 8.8 mag, d~1150 pc continuum Poetzel et al High V Binary system (0.1 sep): FU Ori star + eruptive Herbig Be star of EXor type (Benisty+ 2010) The Herbig component underwent two major outbursts in 2008 and 2010, attributed to enhanced accretion events The binary system is associated to twin jets detected in optical and NIR lines Herbig FU Ori Keck-OSIRIS [FeII] Low V Whelan et al Canovas et al. 2012

10 SPHERE-SVT-P95 proposal on ZCma (PI: S. Antoniucci) SCIENCE CASE ZCMA is a unique laboratory to: 1) investigate connection btw accretion and ejection > by imaging the ejection knots ( mas away) associated to the accretion outbursts to link accretion and ejection events 2) test the magneto-centrifugal scenario for intermediate mass stars > by measuring collimation and accretion/ejection efficiency (Mjet/Macc) 3) test the universality of MHD models > by comparing with jets from low-mass stars (TTSs) 4) investigate the interaction btw the twin jets and the envelope/disks > by taking high angular res images in the line & cont emission OBSERVING MODES Objective: Imaging in Hα, [O I], [Fe II] lines Instruments: ZIMPOL-NB + coro, IRDIS-NB + coro, IFS (+ coro?) Angular resolution: ~20 mas in the optical, ~30-50 mas in the NIR Distance from source: down to ( AU) Integration time: 1 hour per line (~3 hours)

11 Target for EGTO-P94, GTO-P95: The Jet from HD HST + 1 coronagraph Grady et al Apache/GFP + coronagraph [S II] 6731 Å XShooter/VLT - slit offset to avoid the star cont Wassel et al Ellerbroek, Podio et al HD : > observable in Mar Jul R = 6.86 mag, d~120 pc > ideal to observe very close to the source (~6-12 AU) with AO young Herbig AeBe star with disk (cont) + bipolar jet (knots seen in optical+nir lines) periodic ejection events (from proper motion/radial velocity + knots distance > τ ~16 years) optical fading+nir brightening at ejection events > evidence of dust along the jet?

12 GTO-P95 observations of HD (PI: L. Podio) SCIENCE CASE resolve the jet close to the driving source (down to 0.05 =6 AU) > test MHD models infer jet properties: width, density & temperature (from [Fe II]) > jets from intermediate-mass stars vs low-mass stars? infer the mass loss rate > accretion/ejection efficiency dust in the jet (from [Fe II] lines)? > disk shielding? detect new knots > test jet periodicity? detect molecular gas (H2) > wide angle disk-wind? Ellerbroek, Podio et al OBSERVING MODES ZIMPOL + NB filters: imaging in [O I] 6300 Å, Hα 6563 Å > jet width/collimation IRDIS + NB filters: imaging in [Fe II] 1.64 µm, H µm > atomic/molecular jet IFS: [Fe II] 1.25, 1.53, 1.64 µm lines > ne, Te, dust. Accurate continuum subtraction. Coronagraph + AO: image close to the star (~ mas), res down to ~20 mas

13 CONCLUSIONS Structure of jets, launch mechanism : Important clues on disk evolution and planet formation YSO sources of jets are optimally suited for AO coronagraphic imaging and/or IFU jet tracers in the VIS NIR Well doable with SPHERE Need a few hours observation per target

14 OPEN QUESTIONS A few technical aspects: How to use the ETC? It is optimised for planets, output=contrast vs distance Is it enough 1 hr integration per line/target (30 min line + 30 adj cont)? Is it possible to use IRDIS-K (H2 line) with IFS-J-H ([Fe II] lines) simultaneously? Occulting the star IRDIS: 4QPM (IWA~0.05, Visitor) vs ALC (IWA~ , Service) sensitivity losses? Crucial to understand how close to the source we can observe Occulting the star ZIMPOL: 4QPM (IWA~λ/D, no in P95) vs CLC (D~ mas) For jets we use field-stabilized mode?