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Eduardo L. Martín¹, Ramarao Tata², Enrique
Solano¹, Eder Martioli3, Simon Hodgkin4
Daniel Steeghs5
1.- Centro de Astrobiología (INTA-CSIC), Madrid, Spain
2.- Instituto de Astrofísica de Canarias, Tenerife, Spain
3.- Canada-France-Hawaii Telescope
4.- Institute of Astronomy, Cambridge, UK
5.- University of Warwick, UK
Ultracool KIS
Ultracool dwarfs (UCDs): Definition
Ultracool dwarfs: Dwarfs with spectral type
later than M7 (Teff<2600K). Dust grain
condensation in atmospheres (Fe, Al2O3, MgSiO3).
UCDs: photometric variability •
Martin, Zapatero Osorio & Lehto 2001, ApJ, 557, 822
UCDs: photometric variability •
Bailer-Jones & Mundt 2001, A&A, 367, 218
★✪
---------------------------------------------------------Expected Kepler Precision @ Kp=18 in 30 min
Amazing flare in LP412-31 (dM8, Schmidt et al. 2007, AJ, 133, 2258)
First UCD in the Kepler field
UCDs in the Kepler Input Catalog
• UCD identification is very effective using reduced proper motions (Phan Bao et al. 2008, MNRAS, 383, 831).
• H_r=r+5.0*log10(PM)+5.0 > 20
• KIC contains 13 million sources
• i-J>3.9; r-i>2.0; J-K>0.9 + proper motion in KIC = 15 UDC candidates•Proper motions from UKIRT + 2MASS + Poss I, II + DSS = 15 UDC candidates +
UCDs in KIC: Spectroscopic follow-up 5 UCD candidates observed with KPNO 4m Mayall / RcSPEC (August 2011) : 1 L0, 2 M7, 1 M6, 1 M5
11 UCD candidates observed with NOT and TNG in Oct 2011, 13 validated
•
•
•
13/16 confirmed UCDs
UCDs in Kepler FoV: VO approach
• Cross correlation of archives of large-area surveys is very time-consuming task if performed by hand but, on the contrary, it is an approach that perfectly fits in the framework of the Virtual Observatory
• VO ultimate goal: Efficient access and analysis of the information available in the astronomical archives and services.
Std
s
Tools
Science
VO mining of KIS survey
KIS: Kepler-INT survey (Greiss et al. 2012 MNRAS) * 50 sq. deg. 6 million sources; U, g, r, i, Halpha
2MASS Point Source Catalogue. * Whole Sky (41253 sq. deg.). 471 million sources
UCD search: VO tools• The tools: Aladin & TOPCAT
UCDs: VO criteria + VOSA validationAll point sources in KIS with 2MASS counterparts within 10”, but no counterpart within 1”
Color criteria (r-i)>2.0, (J-H) > 0.6 mag
5 new candidates UCD candidates validated with VOSA
UDCs are faint sources for Kepler!
UCDs in Kepler: Conclusions & Prospects 30 UDC candidates found in KIC: spectroscopic follow-up in 2011 confirmed 13/16 candidates
5 additional UDC candidates from KIS correlation with 2MASS using VO tools
GO Cycle 4 program accepted to observe 30 UDCs (GO40030)
Spectroscopic follow-up at KPNO and GTC scheduled in July 2012.
PSF photometric software for deblending faint sources. Photometric precision goal 5 mmag at Kp=19 for low cadence.
Expected results of Kepler observations of UDCs: Characterization of weather patterns; flare duty cycles; rotational periods & constrains on eclipsing binaries and close-in planets.