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NICMOS & VLT Imaging of 2MASSWJ 1207334-393254 (aka 2M1207 ) A Planetary-Mass Companion to a Young Brown Dwarf. Glenn Schneider (Steward Observatory, U. Arizona). First imaging detection of a gravitationally bound, extrasolar, planetary-mass companion. VLT Collaborators C. Dumas (ESO)
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NICMOS & VLT Imaging of 2MASSWJ 1207334-393254 (aka 2M1207) A Planetary-Mass Companion to a Young Brown Dwarf Glenn Schneider (Steward Observatory, U. Arizona) First imaging detection of a gravitationally bound, extrasolar, planetary-mass companion. VLT Collaborators C. Dumas (ESO) G. Chauvin (ESO) HST/GO 10176 Team I. Song, PI (Gemini Obs.) G. Schneider (UofA) B. Zuckerman (UCLA) E. Becklin (UCLA) P. Lowrance (Caltech) B. Macintosh (LLNL) M. Bessell (ANU)
NICMOS CORONAGRAPHIC SURVEY OF 116 NEARBY (20 - 100 pc from Earth) YOUNG (a few million to ~ 100 million years) STARS & BROWN DWARFS STARTED JULY, 2004 (HST cycle 13)* *see: poster # 34 HST/GO 10176 Team I. Song, PI (Gemini Obs.) G. Schneider (UofA) B. Zuckerman (UCLA) E. Becklin (UCLA) P. Lowrance (Caltech) B. Macintosh (LLNL) M. Bessell (ANU)
NICMOS CORONAGRAPHIC SURVEY OF 116 NEARBY (20 - 100 pc from Earth) YOUNG (a few million to ~ 100 million years) STARS & BROWN DWARFS STARTED JULY, 2004 (HST cycle 13) Larger angular separations: - less challenging image contrasts - more accurate photometry
NICMOS CORONAGRAPHIC SURVEY OF 116 NEARBY (20 - 100 pc from Earth) YOUNG (a few million to ~ 100 million years) STARS & BROWN DWARFS STARTED JULY, 2004 (HST cycle 13) Thermally emissive: - INFRARED “bright” from residual heat of formation
NICMOS CORONAGRAPHIC SURVEY OF 116 NEARBY (20 - 100 pc from Earth) YOUNG (a few million to ~ 100 million years) STARS & BROWN DWARFS STARTED JULY, 2004 (HST cycle 13) Including 2MASSWJ 1207334-393254 (2M1207)
NICMOS CORONAGRAPHIC SURVEY OF 116 NEARBY (20 - 100 pc from Earth) YOUNG (a few million to ~ 100 million years) STARS & BROWN DWARFS STARTED JULY, 2004 (HST cycle 13) Program Status: 77% Completed (02 May 2005)
NICMOS CORONAGRAPHIC SURVEY OF 116 NEARBY (20 - 100 pc from Earth) YOUNG (a few million to ~ 100 million years) STARS & BROWN DWARFS STARTED JULY, 2004 (HST cycle 13) • • Identifying individual EGP candidates for astrometric, photometric, spectroscopic follow-up. • • Will provide statistics on EGP population distribution at orbital distances beyond the current reach of Radial Velocity surveys. • • Will inform on minimum mass for Jeans mass fragmentation (e.g., Low & Bell 176 367 (1976), suggested at ~ 7 Mjup), with detection sensitivities in the 1 - 10 Mjup range at 10’s to 100’s of AU.
Oct 2004: A & A, 425, L29 May, 2004 VLT Collaborators Suggested 2M1207: A Giant Planet Candidate Near a Young Brown Dwarf: Direct VLT/NACO* Observations Using IR Wavefront Sensing Giant Planet Companion Candidate VLT/AO TEAM (NACO) G. Chauvin, A.-M. Lagrange, C. Dumas, B. Zuckerman, D. Mouillet, I. Song, J.-L. Beuzit, P. Lowrance “Very faint, very red object @ ~ 780 mas” *NACO/CONICA: (Near-IR camera) Adaptive Optics Configuration NICMOS CORONAGRAPHIC SURVEY OF 116 NEARBY (20 - 100 pc from Earth) YOUNG (a few million to ~ 100 million years) STARS & BROWN DWARFS including 2M1207 STARTED JULY, 2004 (HST cycle 13)
2M1207 TW Hya Assn Member Age: 8 +4/-3 Myrs Distance: 70 ± 20 pc Spectrum: M8.5 25 Jupiter-Mass BD Zuckerman et al 2001 (ApJ 562 87) Gziz 2002 (ApJ 575 484) Ortega et al 2002 (ApJ 575 75) Song et al 2003 (ApJ 559 342) Mohanty et al 2003 (A&A 441 517) Gizis & Bharat 2004 (ApJ 608 113) Sterzik et al 2004 (A&A 427 245) Zuckerman & Song 2004 (ARA&A 42 685) * * d ~ 52 +/-8 pc Mamajek, poster 26 this symposium VLT/NACO Discovery Image (H, Ks, L’)
(revised position & uncertainties)
VLT/NACO OBSERVATIONS (APRIL/JUNE 2004) - IMAGING IN 3 SPECTRAL BANDS > 1.6 mm (H, Ks, L’) “Colors” suggestive of Young Extra-Solar Giant Planet (EGP) - GPCC UNDETECTED IN 1.26 mm J-band Source too faint for declining AO performance at short l’s - LOW RESOLUTION SPECTROSCOPY @ 1.5 - 1.8 mm With broad absorption indicative of H20, expected for young EGPs SUGGESTED: Mass = 5 ± 2 x Jupiter, Temperature = 1250K ± 200K VLT/AO TEAM (NACO) G. Chauvin (ESO), A.-M. Lagrange (Obs. de Grenoble) C. Dumas (ESO), B. Zuckerman (UCLA), D. Mouillet (Observatoire Midi-Pyrénées), I. Song (Gemini Observatory), J.-L. Beuzit (Observatoire de Grenoble), P. Lowrance (SSC/IPAC)
2M1207 Proper Motion: ~ (-55 ma, -24 md)* mas/year Rapid Common PM Follow-up * Scholz et al (2005)” (-78 +/- 11 ma, -24 +/ -9 md) mas/year
Location of 2M1207 Giant Planet Companion Candidate 0.774” 54 AU @ 70 pc (projected on sky) HST/NICMOS CAMERA 1 FOLLOW-UP IMAGING Epoch 2: 08/28/2004 (4 month astrometric baseline w.r.t VLT) PSF subtracted image F090M (0.9mm) F110M (1.1mm) F160W (1.6mm) 40 +/- 6 AU @ 52 +/- 8 pc
At 0.9 microns the 2M1207b: - has an apparent magnitude of +22.3 (08/28/2004) - is 720 times fainter than 2M1207 (mag +15.20) - is 44 times fainter than it is at 1.6 microns NICMOS observations exploit the stability of the HST Point Spread Function to reduce the background light from 2M1207A and improve the image contrasts. F090M(0.9mm) F110M(1.1mm) F160W(1.6mm) 2M1207b is 774 mas from 2M1207A
HST/NICMOS Camera 1 Observations of 2M1207 Two Orbits at Two Field Orientations 9.9° Roll - Constrained by Available Guide Stars F090M(0.9mm) F110M(1.1mm) F160W(1.6mm) 4-Point Dither Combined Images ROLL ORIENTATION # 1
HST/NICMOS Camera 1 Observations of 2M1207 Two Orbits at Two Field Orientations 9.9° Roll - Constrained by Available Guide Stars F090M(0.9mm) F110M(1.1mm) F160W(1.6mm) 4-Point Dither Combined Images ROLL ORIENTATION # 2
HST/NICMOS Camera 1 Observations of 2M1207 F090M(0.9mm) F110M(1.1mm) F160W(1.6mm) 4-Point Dither Combined Images DIFFERENCE IMAGE
HST/NICMOS Camera 1 Observations of 2M1207 F090M(0.9mm) F110M(1.1mm) F160W(1.6mm) 4-Point Dither Combined Images SIMULTANEOUS BEST-FIT OPTICAL MODEL
HST/NICMOS Camera 1 Observations of 2M1207 F090M(0.9mm) F110M(1.1mm) F160W(1.6mm) 4-Point Dither Combined Images BEST-FIT MODEL SUBTRACTIONS - Negative Image Nulling
HST/NICMOS Camera 1 Observations of 2M1207 F090M(0.9mm) F110M(1.1mm) F160W(1.6mm) BEST-FIT MODEL SUBTRACTIONS
HST/NICMOS Camera 1 Observations of 2M1207 INVERT SECOND ORIENTATION
HST/NICMOS Camera 1 Observations of 2M1207 ROTATE TO SAME SKY ORIENTATION
HST/NICMOS Camera 1 Observations of 2M1207 ROTATE TO SAME SKY ORIENTATION
HST/NICMOS Camera 1 Observations of 2M1207 F090M(0.9mm) F110M(1.1mm) F160W(1.6mm) 4-Point Dither Combined Images COMBINATION IMAGES
BLUE = F090M(0.9mm) GREEN=F110M(1.1mm) RED=F160W(1.6mm) Epoch 2 astrometry - NICMOS -Schneider et al 2004 AAS 205 114
Common Proper Motion Probability*: 2.6s (99.1%) -Schneider et al 2004 AAS 205 114 BLUE = F090M(0.9mm) GREEN=F110M(1.1mm) RED=F160W(1.6mm) *Predicated on earlier, more uncertain, PM for 2M1207 than Scholz et al 2005 (shown here).
} HST BOTH } VLT Temp. = 2750 K Temp. < 1200 K ~ VLT/NACO & HST/NICMOS PHOTOMETRY 4/27/2004 & 8/28/2004 APPARENT MAGNITUDE waveln 2M1207b 2M1207A Dmag 0.9mm: +22.34 ± 0.35 +15.20 ± 0.03 +7.14 ± 0.35 1.1mm: +20.16 ± 0.15 +13.29 ± 0.03 +7.02 ± 0.15 1.6mm: +18.24 ± 0.02 +12.62 ± 0.02 +5.62 ± 0.03 2.2mm: +16.93 ± 0.11 +11.95 ± 0.03 +4.98 ± 0.11 3.8mm: +15.28 ± 0.14 +11.38 ± 0.14 +3.90 ± 0.17
. . 2M1207A 2M1207b NICMOS Companion Detection Limit (M type primary) Cooling Curves for Substellar Objects 0 Evolution of M Dwarf Stars, Brown Dwarfs and Giant Planets (from Adam Burrows) STARS (Hydrogen burning) -2 200M jup L/Lsum 80M -4 jup BROWN DWARFS (Deuterium burning) 10 PLANETS Log -6 sun 14M jup -8 JUPITER SATURN -10 6 10 9 8 7 Log Age (years) 10
VLT/SPECTRUM HST/NICMOS CAMERA 1 OBSERVATIONS (AUGUST 2004) : - IMAGING IN 3 SPECTRAL BANDS < 1.6 mm (H, 1.1 & 0.9 mm) Provided short wavelength diagnostic flux densities (& color indices) - 2M1207B IMAGED & PHOTOMETERED IN ALL BANDS “Colors” and Flux Densities Consistent with Young EGP Mass Object THEORETICAL EGP SPECTRA (A. Burrows) IMPLICATED: Temperature < 1200K, Mass < 5 Jupiter. ~ ~
Epoch 3 & 4 astrometry - VLT (Chauvin et al 2005 astro-ph 4/29/05)
Location 2M1207A 2M1207b 0.774” 54 AU @ 70 pc (projected on sky) HST/NICMOS CAMERA 1 2nd FOLLOW-UP IMAGING Epoch 5: 26 APRIL 2005 12 month astrometric baseline w.r.t 1st VLT image 7 month astrometric baseline w.r.t. 1st NICMOS image PSF subtracted images F090M (0.9mm) F145M (1.45mm) F160W (1.6mm)
HST/NICMOS CAMERA 1 2nd FOLLOW-UP IMAGING F145M F145M (1.45mm) imaging in H20 absorption band THEORETICAL EGP SPECTRA (A. Burrows)
HST/NICMOS CAMERA 1 2nd FOLLOW-UP IMAGING 2M1207A/b - 26 APR 05 NICMOS F160W (1.6mm) -2 to +2 ADU/second/pixel
HST/NICMOS CAMERA 1 2nd FOLLOW-UP IMAGING 2M1207A/b - 26 APR 05 NICMOS F145M (1.45mm) -0.4 to + 0.4 ADU/second/pixel
HST/NICMOS CAMERA 1 2nd FOLLOW-UP IMAGING 2M1207A/b - 26 APR 05 NICMOS F090M (0.9mm) -0.03 to + 0.03 ADU/second/pixel
HST/NICMOS CAMERA 1 2nd FOLLOW-UP IMAGING 2M1207A/b - 26 APR 05 NICMOS F090M (0.9mm) -0.03 to + 0.03 ADU/second/pixel
HST/NICMOS CAMERA 1 2nd FOLLOW-UP IMAGING F145M (1.45mm) imaging in H20 absorption band 2M1207b APPARENT MAGNITUDES mm 04/27/04 VLT08/28/2004 HST04/26/2005 HST 0.90 +22.34 ± 0.35 +22.58 ± 0.35 1.10 +20.61 ± 0.15 1.45 +19.05 ± 0.03 1.60 +18.24 ± 0.02 +18.27 ± 0.02 2.20 +16.93 ± 0.11 3.90 +15.28 ± 0.14
Epoch 5 astrometry - NICMOS Unequivocal common P.M.
The 2M1207 System MASS(A) ~ 25 Mjup, MASS(b) < ~ 5 Mjup Model Dependent: Burrows et al 1997, Chabrier et al 2000, Baraffe et al 2001 How “GOOD” are Non-Dynamical Mass Estimates? (Corollary: How “good” are the models?) 2M1207A mass derived from surface gravity from spectral line shapes (Mohantey et al 2003*) with distance and Teff get luminosity and radius. Distance uncertain by ~ 30% (70 ± 20 pc). Need trigonometric parallax! *For upper Sco Baraffe may overestimate mass, so 2M1207b < 5 Mjup? AB Dor. Models suggest BD mass. Close et al (2005) dynamical observations suggests models underestimate substellar masses. AB Dor at Stellar/BD boundary. Gabor/Mohantey suggest models will underestimate masses in that domain but may overestimate planetary masses.
Thinking toward the future… Mean Orbital Motion = 14.4’/year (circular, face on): ~ 3.5 mas of apparent motion/yr The 2M1207 System MASS(A) ~ 25 Mjup, MASS(b) < ~ 5 Mjup Model Dependent: Burrows et al 1997, Chabrier et al 2000, Baraffe et al 2001 amin ~ 40 AU*, Pmin ~ 1500 yr * for 52 pc HST/NICMOS differential astrometric precison ~ 2 mas. Annual measures with 1s precision w.r.t. orbital motion. (1° around the orbit in 5 years…)
(Trivial?) Question in Conclusion: Nomenclature: 2MASSWJ 1207334-393254b 2MASSWJ 1207334-393254A 2MASSWJ 1207334-393254b Field Star It is of Planetary Mass, but is it a “PLANET”? (how did it form: collision, embryonic-ejection, core accretion, grav. collapse/ fragmentation, photo-evap in massive SF association?) 2M1207b 2b Toobe Or… not to be?
Question in Conclusion: 2MASSWJ 1207334-393254A 2MASSWJ 1207334-393254b Field Star It is of Planetary Mass, but Is it a “PLANET”? (how did it form: collision, embryonic-ejection, core accretion, grav. collapse/ fragmentation, photo-evap in massive SF association?) That is the question!
WHAT NEXT? 0.9mm 1.1mm 1.6mm HST CYLE 14 - GO/10538 PSF-Subtracted Grism Spectrophotometry 0.8 – 1.2 mm (40 ksec) & 1.1 – 1.8 mm (10 ksec) in 18 HST Orbits Near-IR Spectrophotometry of 2MASSWJ 1207334-393254b
NICMOS & VLT Imaging of 2MASSWJ 1207334-393254 (aka 2M1207) A Planetary-Mass Companion to a Young Brown Dwarf Glenn Schneider (Steward Observatory, U. Arizona) VLT Collaborators C. Dumas (ESO) G. Chauvin (ESO) HST/GO 10176 Team I. Song, PI (Gemini Obs.) G. Schneider (UofA) B. Zuckerman (UCLA) E. Becklin (UCLA) P. Lowrance (Caltech) B. Macintosh (LLNL) M. Bessell (ANU)