Galactic Science: Star and Planet Formation Michael Liu Andrea Ghez, Tom Greene, Lynne Hillenbrand, Jessica Lu, Bruce Macintosh, Stan Metchev, Nevin Weinberg

Galactic Science:Galactic Science:Star and Planet FormationStar and Planet Formation

Michael Liu Michael Liu

Andrea Ghez, Tom Greene, Lynne Hillenbrand, Andrea Ghez, Tom Greene, Lynne Hillenbrand, Jessica Lu, Bruce Macintosh, Stan Metchev, Jessica Lu, Bruce Macintosh, Stan Metchev,

Nevin WeinbergNevin Weinberg

Keck SSC meeting, June 2006Keck SSC meeting, June 2006

M. Liu (IfA/Hawaii)M. Liu (IfA/Hawaii) 22

Galactic Science:Galactic Science:Key Science CasesKey Science Cases

1.1. Extrasolar Planets Extrasolar Planets (Liu, Macintosh)(Liu, Macintosh)

2.2. Debris Disks Debris Disks (Metchev, Liu)(Metchev, Liu)

3.3. Protostars Protostars (Hillenbrand, Greene)(Hillenbrand, Greene)

4.4. Galactic Center Galactic Center (Weinberg, Ghez, Lu)(Weinberg, Ghez, Lu)


AO is critical for star/planet formationAO is critical for star/planet formation

There are/will be numerous wide-field surveys of There are/will be numerous wide-field surveys of the sky for finding young stars of various ages: the sky for finding young stars of various ages: IRAS, Hipparcos, Chandra, Spitzer, JCMT/SCUBA-2,IRAS, Hipparcos, Chandra, Spitzer, JCMT/SCUBA-2,Pan-STARRS, etc.Pan-STARRS, etc.

NGC 1333: 34’x26’Spitzer/IRAC

Follow-up observations of the relevant physical Follow-up observations of the relevant physical scales are scales are <1 arcsec<1 arcsec: : angular resolution & high contrast are criticalangular resolution & high contrast are critical


Why do we need NGAO?Why do we need NGAO?

• Very high-contrast near-IR imagingVery high-contrast near-IR imagingdirectly image planets and debris disksdirectly image planets and debris disks

• Large sky coverageLarge sky coveragestudy stars over a very wide range of masses & agesstudy stars over a very wide range of masses & ages

• Multi-band optical Multi-band optical andand IR wavelengths IR wavelengthsdetermine properties & evolution of circumstellar materialdetermine properties & evolution of circumstellar material


Obligatory star & planet formation slide




Resolving the protostellar Resolving the protostellar environmentenvironment

Disk+Envelope DensityTemperature Dist.Use observed

integrated-light SEDs + high

resolution images to study the

evolution of the youngest stars.

= +


NGAO optical imaging of protostarsNGAO optical imaging of protostars• Simulated I-band (scattered light) image of a Simulated I-band (scattered light) image of a

protostar with a massive envelope & disk at protostar with a massive envelope & disk at 1 kpc1 kpc

NGAO provides highest angular resolution of any filled-aperture telescope (and complementary to

ALMA for this science).

Model image HST ACS/HRC(70 AU resolution)

Keck NGAO(25 AU resolution)




Debris Disks: Extrasolar analogs to Debris Disks: Extrasolar analogs to the asteroid & Kuiper Beltthe asteroid & Kuiper Belt

• structurestructure• compositioncomposition• evolutionevolution• low-mass planetslow-mass planets

Keck NGS: H-bandResolved disks are a goldmine for studying:

100’s of these known from integrated light, but only ~12 resolved to date (2 by AO).


Debris disks studies with NGAODebris disks studies with NGAOsimulated 3-hour H-band integration simulated 3-hour H-band integration

of massive Kuiper Belt in the Pleiades (120 Myr, 130 pc)of massive Kuiper Belt in the Pleiades (120 Myr, 130 pc)

Undetectable Neptune with 1:1 resonant dust ring

NGAO could image many (10s-100s) analogs to the young solar

system, study other Kuiper Belts & low-

mass planets

Solar system model High Strehl NGAO Keck AO today




Planets around VLM stars & brown dwarfsPlanets around VLM stars & brown dwarfs

• Direct imaging and Direct imaging and spectroscopy of planetsspectroscopy of planets easier around low-mass easier around low-mass stars and brown dwarfs.stars and brown dwarfs.

• Study objects with Study objects with SEDs & SEDs & atmospheresatmospheres similar to similar to “regular” exoplanets, but “regular” exoplanets, but perhaps with diff origin.perhaps with diff origin.

• High contrast LGSHigh contrast LGS + + IR tiptiltIR tiptilt needed. needed.

~5 MJup?

~25 MJup

Chauvin et al (2005): VLT AO (IR WFS)


NGAO: Planet detection sensitivityNGAO: Planet detection sensitivity• Very high contrast in near-IR enables imaging of Jovian-Very high contrast in near-IR enables imaging of Jovian-

mass planets around mass planets around low-mass starslow-mass stars and and brown dwarfsbrown dwarfs..

• This can only be This can only be done by NGAO.done by NGAO. The The stars are too optically stars are too optically faint for ExAO systems faint for ExAO systems (I<8-9). (I<8-9).

• A unique avenue for A unique avenue for testing planet testing planet formation models, by formation models, by using a wide range using a wide range of stellar host mass.of stellar host mass.


NGAO opens a unique realm for NGAO opens a unique realm for high contrast studies for a high contrast studies for a broadbroad range range

of science programs.of science programs.

AO systemAO system ContrastContrast

Extreme AOExtreme AOv.v.bright stars onlybright stars only

101077–10–1088

Keck NGAOKeck NGAOmany targetsmany targets 101055–10–1066


Why do we need NGAO?Why do we need NGAO?

• Very high-contrast near-IR imagingVery high-contrast near-IR imagingdirectly image planets and debris disksdirectly image planets and debris disks

• Large sky coverageLarge sky coveragestudy stars over a very wide range of masses & agesstudy stars over a very wide range of masses & ages

• Multi-band optical Multi-band optical andand IR wavelengths IR wavelengthsdetermine properties & evolution of circumstellar materialdetermine properties & evolution of circumstellar material


The EndThe End

Documents

Galactic Science: Star and Planet Formation Michael Liu Andrea Ghez, Tom Greene, Lynne Hillenbrand, Jessica Lu, Bruce Macintosh, Stan Metchev, Nevin Weinberg