1 / 33

Galactic Star Formation Science

Galactic Star Formation Science. with Integral Field Spectroscopy. Tracy Beck, STScI. Galactic Star Formation Science with Integral Field Spectroscopy. Introduction to the formation of sun-like stars in the Milky Way Studies of star formation (SF) with IFUs

frey
Download Presentation

Galactic Star Formation Science

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Galactic Star Formation Science with Integral Field Spectroscopy Tracy Beck, STScI

  2. Galactic Star Formation Science with Integral Field Spectroscopy • Introduction to the formation of sun-like stars in the Milky Way • Studies of star formation (SF) with IFUs • First uses of IFUs for SF science • Herbig Haro Objects • Young Star Binaries • Star Formation at high contrast with IFUs: A Search for IR H2 Emission from the Disks of Young Stars • Cutting Edge Science: Laser-Fed AO IFU spectroscopy of young stars • Prospects for JWST and the ELTs

  3. Formation of Sun-like Stars in the Milky Way Sub-mm continuum of protostellar cores Shirley et al. (2000)

  4. Formation of Sun-like stars in the Milky Way Young stars with Circumstellar disks + extended Envelopes (“Class I” Protostars) HST NICMOS Imaging of Protostars (Padgett et al. 1999)

  5. Formation of Sun-like stars in the Milky Way Young stars with Circumstellar disks, no envelope material left (“Class II” Protostars, “Classical” T Tauri Stars) Orion Proplyds O’Dell & Wen (1994)

  6. Formation of Sun-like stars in the Milky Way Beta Pic Debris Disk Dust disk dissipates in <1Gyr timescale Meyer et al. (2008)

  7. Formation of Sun-like stars in the Milky Way “Class II” Protostars with Disks + Outflows – “Classical T Tauri Stars”

  8. IFUs in Star Formation Science MPE 3D w/ Calar Alto (3.5m) H and K-band Observations of T Tau Herbst et al. “A Near-Infrared Spectral Imaging Study of T Tau” 1996 AJ v.111, 2403 8”

  9. IFUs in Star Formation Science Lavalley et al. “Sub-arcsecond morphology and kinematics of the DG Tauri jet in the [O I]λ6300 line” 1997 A&A v.327, 671 IFUs are very powerful tools for spatially resolving emission line structures in the environments of bright T Tauri Stars

  10. HerbigHaro Objects HH 111 • HH Objects: • optical/infrared tracers of YSO jets, seen where jets from young stars plow into ambient cloud material and shock the gas into emission • Pure emission line objects • viewed in optical/infrared permitted and forbidden transitions – Ha, [O I], [N II], [S II], [FeII], trace atomic gas excited by shocks • Shock-excited H2 emission in the IR  Natural IFU Sources Beck et al. 2004, 2007, Lopez et al. 2008, 2010 Giannini et al. 2008 HH 46/47

  11. Wings of the Bow Shock Herbig Haro Objects • HH 99B: • Very sensitive VLT + SINFONI observations • 170+ Emission lines detected • Many very high excitation lines of H2 and [Fe II] • Bow-shock apex shows extremely high temperature - T~6000K - revealing that the H2 molecule persists in these very high temperature regions Giannini et al. “Near-infrared, IFU spectroscopy unravels the bow-shock HH99B“ 2008, A&A v.481, 123 H2 1-0 S(1) 2.12mm H2 2-1S(17) 1.758mm Head of the Bow Shock [Fe II] 1.644 mm [Fe II] 1.749 mm HI Pab 1.28 mm [P II] 1.188 mm

  12. Young Star Binaries • Most stars (50-60%) form as binary or higher order multiple systems • Understand young star binary characteristics, particularly disk and mass accretion evolution • The more massive primary star often has more active mass accretion, indicating a larger circumstellar disk reservoir of mass. I.e., preferential accretion from circumsystem material onto the more massive star in a binary • Spatially Resolved Observations of Young Star binaries 0.”1 to ~1” separations, Programs ongoing using NIFS, SINFONI & OSIRIS

  13. Young Star Binaries – Z CMa • Protostellar B star (Herbig Be star) primary, FU Ori eruptive variable companion • System has become a prototype for understanding eruptive mass accretion in young star binaries • OASIS observations in [OI] 6300A Garcia et al. “Spatially resolved spectroscopy of Z Canis Majoris components” 1999, A&A v.346, 892 0.”1 binary observed with OASIS – 0.”11 microlenses!

  14. Young Star Binaries – Z CMa • Keck OSIRIS [Fe II] 1.644mm observations of Z Cma Whelan et al. “The 2008 Outburst of Z CMa: The First Detection of Twin Jets” 2010, ApJL v.720,L119 • The Massive Herbig Be star does drive the parsec scale outflow! • The companion is discovered for the first time to drive its own small scale jet • First detection of a collimated jet from a FU Ori outbursting variable star!

  15. High Contrast IFU Spectroscopy in Star Formation – Gas in Circumstellar Disks HH 30 • Dust in Circumstellar Disks – Traced by infrared excess • Emission, seen in scattered light images of T Tauri stars • Gas in Circumstellar Disks – As much as 99% of the mass in circumstellar disks is in GAS not DUST • Disk Gas is traced by: • mm molecular observations of cold outer disk gas • IR emission species trace warm gas from ~terrestrial regions of disks • Most studies cannot spatially resolve the gas in the inner disk regions and measure trace components of the disks, ~70% of the disk by mass is in H2

  16. The Search for IR Molecular Hydrogen Gas in Young Star Disks FWHM ~0.”1 Gemini + NIFS IFU observations of six T Tauri Stars – all known to drive YSO outflows K-band Continuum Images Beck et al. “Spatially Resolved Molecular Hydrogen in the Inner 200 AU Environments of T Tauri Stars” 2008 ApJ, v.676, 472

  17. The Search for IR Molecular Hydrogen Gas in Young Star Disks From Classical T Tauri stars w/ outflows, H2 arises from shocked emission surrounding the HH flows Herbig Haro Flows Beck et al. “Spatially Resolved Molecular Hydrogen in the Inner 200 AU Environments of T Tauri Stars” 2008 ApJ, v.676, 472

  18. IFU Observations of T Tau Across a Decade… Herbst et al. 1996 MPE 3D Data from Calar Alto 3.5m Jan. 1995 Beck et al. 2008 NIFS Data from Gemini-N 8m Oct. 2005

  19. The Search for Molecular Hydrogen Gas in Young Star Disks T Tau in [Fe II] • VLT + SINFONI Observations of T Tau, detection of H2 from the face-on disk around T Tau N? Gustofsson et al. “Spatially resolved H2 emission from the disk around T Tau N” 2008 H2 Emission Flux H2 Velocity H2 Velocity Dispersion

  20. Where is the IR Molecular Hydrogen Gas in Young Star Disks? • Doing a Gemini + NIFS IFU survey of additional young stars, more than doubling the past sample – this includes stars that have evidence for dust disk gaps (from IR SED shapes), and/or “disk-like” H2 from past long-slit observations Highlight = GG Tau A, 0.”3 binary young star, with the prototypical “Circumbinary Ring” of dust (Roddier et al. 1996) * 3” Circumbinary Ring seen in scattered light T. Beck, J. Bary et al. “The Search for Spatially Resolved IR H2 from the Disks of Classical T Tauri Stars” (in prep.) Subaru CIAO Observations of GG Tau A

  21. The Search for IR H2 from a Disk High Contrast for Star Formation IR Spectrum of GG Tau A – typical of young stars Brg NIFS 2.12mm continuum image of the 0.”3 GG Tau A binary H2?? Fe I H2!! Looking for a signal of ~few 100 cts, on a continuum of 30K+ cts, with a photospheric Fe I feature in the way!

  22. The Search for IR Molecular Hydrogen Gas in Young Star Disks T. Beck, J. Bary et al. “The Search for Spatially Resolved IR H2 from the Disks of Classical T Tauri Stars” (in prep.)

  23. The Search for IR Molecular Hydrogen Gas in Young Star Disks • H2 Emission in the Environment of GG Tau A • H2 2-1 S(1) / 1-0 S(1) line ratio not indicative of fluorescent pumping by UV photons, is consistent with X-ray heating of the gas • Gas/Dust in Protostellar binaries should NOT exist (Artymowicz & Lubow 1994): • Circumstellar: at spatial locations beyond ~1/3 of the semi-major axis of the binary (disk truncation) • Circumbinary: at spatial locations within ~3x the semi-major axis of the binary (gap clearing) • Clearing timescale ~100’s of years! H2 1-0 S(1) @ 2.12mm T. Beck, J. Bary et al. “The Search for Spatially Resolved IR H2 from the Disks of Classical T Tauri Stars” (in prep.)

  24. The Search for IR Molecular Hydrogen Gas in Young Star Disks 40AU – Pluto’s semi-major axis H2 1-0 Q(1) @ 2.40mm H2 1-0 S(1) @ 2.12mm T. Beck, J. Bary et al. “The Search for Spatially Resolved IR H2 from the Disks of Classical T Tauri Stars” (in prep.)

  25. Cutting Edge SF Science: Laser-Fed AO Observations of Young Stars Pushing to Higher Mass: • Comparably few detailed spatially resolved observations of collimated outflows toward protostars with higher mass than the sun-like T Tauris. • Keck Observatory LGS AO + OSIRIS IFU Observations of the very young Herbig Ae star LkHa 233 • Investigate whether the similarity on large spatial scales between outflows from T Tauri and Herbig Ae stars still holds true on finer spatial scales. Perrin et al. “Laser Guide Star Adaptive Optics Integral Field Spectroscopy of a Tightly Collimated Bipolar Jet from the Herbig Ae star LkHa 233” 2007 ApJ, v.670, 499

  26. Cutting Edge SF Science: Laser-Fed AO Observations of Young Stars Perrin et al. “Laser Guide Star Adaptive Optics Integral Field Spectroscopy of a Tightly Collimated Bipolar Jet from the Herbig Ae star LkHa 233” 2007 ApJ, v.670, 499

  27. Cutting Edge SF Science: Laser-Fed AO IFU Observations of Young Stars Pushing to Lower Mass: • IRAS 04158+2805 = young proto-object in the Taurus SFR (d~140pc) • Seen in the optical largely in scattered light, with a ‘bipolar’ nebula structure typical of opaque disk material along the mid-plane (Glauser et al. ’08), interpreted as a source with a disk inclined by ~63o • YOUNG! (<~1Myo!) w./ M6 type, commonly adopted SpT for young BD limit • HR Diagram fitting = substellar ~0.05Msolar (large uncertainty in models) • Andrews et al ‘08 detected the disk in sub-mm, high spatial resolution dust continuum and CO gas! extends out to >~500AU from the central source - MASSIVE disk with ~1000+ AU total extent! • Stellar mass estimate + extended massive disk! – Mdisk / Mstar ~15-20%! HST Image From Glauser et al. 2008 Beck et al. “Laser Fed Adaptive Optics Imaging Spectroscopy of the Candidate Proto-Brown Dwarf IRAS 04158+2805” in Prep.

  28. Laser-fed AO Spectral Imaging, IRAS 04158+2805 100 AU 2m K-band (Scattered Light!) 2.12m H2 (Wide-Angle Outflow!) 1.644m [Fe II] (Jet!) • Gemini LGS AO w/ NIFS = Goal - Determine if H2 gas traces disk material in the BD candidate environment - it doesn’t! • Data reveals fspatially resolved 2-D spectral images of a well collimated jet from a very young BD candidate • BLUE-shifted, collimated [Fe II] jet associated with the brighter lobe of the scattered light nebulosity - no redshifted jet detected • Jet Orientation consistent w/ 63o viewing disk inclination Beck et al. “Laser Fed Adaptive Optics Imaging Spectroscopy of the Candidate Proto-Brown Dwarf IRAS 04158+2805” in Prep.

  29. Laser-Fed Spectral Imaging of BD Environments • Laser-Fed AO on large ground-based telescopes is a powerful means to reveal the inner environments of BDs at high spatial resolution using IR emission lines… • Complication = BDs are optically very faint, but you need an optical tip-tilt guide star! (TTGS) • Observations of IRAS 04158+2805 were only possible with Gemini +LGS AO because of the nearby r~17.6 magnitude guide star TTGS r~17.6mag IRAS 04158+2805 K~11.6 mag, R~21 AO TTGS Area Gemini Observing Tool View

  30. The Future: SF Science with the JWST and ELT IFUs FAINTER! More Distant– Probe the Star formation process to low mass M stars, approaching the BD limit in the LMC and SMC! Younger – Sun-Like stars at earlier epochs of formation – the “Class I” phase w/ envelope material remaining, or even younger! Lower Mass – BDs and Free-Floating Planets in nearby star forming regions like Taurus and Orion! Higher Mass – Massive O&B stars form in very dense cocoons of gas+dust, pierce through the extinction to see the forming stars!

  31. Spectral Imaging of young Star Environments with JWST • The James Webb Space Telescope - operating at L2 in ~2014 • 6.5m Segmented Primary • 4 Science Instruments: • NIRCam - Near-InfraRed Camera • NIRSpec - Near-InfraRed Spectrograph w/ IFU! • TFI - Tunable Filter Imager • MIRI - Mid-InfraRed Instrument w/ IFU The James Webb Space Telescope A schematic view of the JWST focal plane, including the placement of the science entrance apertures for each instrument. NIRSpec and MIRI have Integral Field Units for very sensitive high-contrast spectral imaging of young star environments.

  32. The Future: SF Science with IFUs on the ELTs Nearby T Tauri stars are bright for large aperture telescopes – but we really need the ELT spatial resolution to push our observations to the ~Jupiter environs! GMT For Kinematics and spectral line detection/characterization, star formation science greatly benefits from HIGH spectral resolution! (R~20,000 or greater) R~27,000 Mandell et al. (2009) When considering properties for IFUs for large telescopes, please don’t forget about star formation science! & Consider a high spectral resolution IFU mode for the IR…!! TMT

  33. The Future: Next Generation Observations of T Tau? ? Herbst et al. 1996 Data from Jan. 1995 Beck et al. 2008 Data from Oct. 2005 Next Generation IFU View of T Tau THANKS!! For Your Attention!

More Related