1. Observing Very Young Stars with GPI
Quinn Konopacky, Bruce Macintosh, Marshall Perrin,
Jenny Patience,
et al.

2. Stars younger than the primary GPI sample (<10 Myr) represent an interesting population for planet detection with GPI.
Star forming regions > 100 pc away - non-ideal GPI targets
Scientific payoff of planet detection great
Would reveal planets early in evolution
Allow for potential comparisons to models of planet formation at interesting ages

3. The brightest stars in young star forming regions are potentially accessible with GPI.
Will not represent statistically complete sample, but physical properties of young planets interesting individually
Age spreads of young clusters often smaller than typical GPI target
Might expect bright, young stars to be analogous to systems like HR 8799 and Fomalhaut
2MASS image of young (~2 Myr) A5 star R Coronae Australis

4. Using various catalogs, a plausible target list was generated.
Requirement that I < 11
Initial list culled from Herbig & Bell (1988) catalog
Supplemented with more recent catalogs identifying additional members of southern star forming regions
R Coronae Australis Region

5. Over 100 targets identified in ~7 regions.
Average distance ~150 pc
I-band magnitudes between 7 and 11
Interesting regions of separation space are probable
50% known binary fraction in sample

6. Over 100 targets identified in ~7 regions.
Average distance ~150 pc
I-band magnitudes between 7 and 11
Interesting regions of separation space are probable
50% known binary fraction in sample
Fomalhaut b
HR 8799b
Neptune
HR 8799d

7. Sample sources have a range of properties.
Both cTTS and wTTS
Range of spectral types
Bump at K-type likely due to unresolved binarity or misidentification
Some transition disk candidates

8. Contrast curves and the GPI DST are used to determine what mass of planets are detectable.
HR 8799b+c
Fomalhaut b
For I < 9 magnitude cases, hot start models:
For star like R Cr Aus (d = 130 pc), possible to detect planets as small as 1 MJ assuming
All undetectable with cold start model
I = 9; Distance = 130 pc; Age = 3 Myr
Hot Start Models, Fortney et al. 2008

9. Example of I=9.0 source with DST shows relative ease of detection of HR 8799b-like object.
Used properties of R Cr Aus Star with I~9, H~7.1, Spectral Type = F5
Possibly visible in individual 30 second exposure
Single 30 second exposure

10. For I~11, magnitude cutoff approximated with DST.
Same level of SNR on companion source ~1-2 mags brighter than I=9 case
Mass limit assuming hot start ~2-3 MJup for these fainter guide stars
Single 30 second exposure

11. Other interesting science can be addressed with this sample.
Young stellar disks
Can investigate transition disk phenomenon
Espaillat et al. 2007
Simulated observation of Herbig Ae star HD , courtesy of Marshall Perrin

12. Other interesting science can be addressed with this sample.
Large mass ratio binaries
Essentially unprobed by multiplicity surveys
Discovery can constrain star formation scenarios and brown dwarf formation scenarios
Bate 2009
Hinkley et al. 2010

13. Summary and Possible Proposal Thoughts
Sufficient very young (age < 10 Myr) are observable with GPI to make for interesting sample
Proposal should be separate from main campaign
Combine with 5-20 Myr sample for more targets?
Thoughts/suggestions welcomed!
Chamaeleon I Complex
European Southern Observatory/VLT UT1+FORS1