MOTIVATION TO DETECT PROTOPLANETS: THOUSANDS OF GAS-RICH EXOPLANETS ARE KNOWN TODAY. YET UNTIL RECENTLY NONE OF THESE WERE YOUNG FORMING/ACCRETING "PROTOPLANETS". MULTI WAVELENGTH OBSERVATIONS (AO AND JWST) OF SUCH PROTOPLANETS ARE THE BEST APPROACH TO UNRAVELING THE MYSTERY OF PLANET FORMATION. TECHNICAL BACKGROUND OF THE MAGAO INSTRUMENT: THE PI AND HIS TEAM HAVE BUILT AND COMMISSIONED AN ADVANCED ADAPTIVE OPTICS (AO) SYSTEM AT THE 6.5-M MAGELLAN CLAY TELESCOPE AT LAS CAMPANAS OBSERVATORY CHILE. THIS SYSTEM IS CALLED MAGAO (PI LAIRD CLOSE) AND IT USES AN ADAPTIVE SECONDARY MIRROR (ASM) WITH 585 ACTUATORS TO APPLY THE CORRECTION MEASURED BY ITS HIGHORDER PYRAMID WAVEFRONT SENSOR (PWFS) 1000 TIMES EACH SECOND. BECAUSE WE CAN CORRECT AT WAVELENGTHS AS SHORT AS H-ALPHA (656.3 NM) THE MAGAO SYSTEM REGULARLY PRODUCES THE HIGHEST-SPATIAL-RESOLUTION DEEP IMAGES TO DATE. MAGAO HAS BEEN ON-SKY OVER 160 NIGHTS NOW AND HAS BEEN IN REGULAR SCIENCE OPERATIONS AT MAGELLAN FOR 3 YEARS. MAGAO IS THE ONLY TELESCOPIC SYSTEM (ON THE GROUND OR SPACE) THAT HAS PUBLISHED HIGH SPATIAL RESOLUTION<0.03 ARCSEC (<30 MAS) IMAGES AT THE STRONGEST HYDROGEN GAS ACCRETION EMISSION LINE: H-ALPHA (CLOSE ET AL. 2013). JUST RECENTLY (FEB 2017) THE TEAM COMMISSIONED THEIR "SDI+" OPTICAL DEVICE THAT ENABLES VERY HIGHCONTRAST HIGH-SPATIAL RESOLUTION IMAGES (PLANET/STAR=10^-3 AT 80 MAS; 10^-4 AT 100 MAS) AT H-ALPHA. WITH THE (NOW OUTDATED) SDI DEVICE THIS TEAM MADE THE FIRST DEFINITE DETECTION OF ACCRETING PROTOPLANETS AT H-ALPHA IN THE GAP OF THE LKCA 15 TRANSITIONAL DISK (SALLUM FOLLETTE ET AL. NOV 19 2015 ISSUE OF NATURE). THEIR NEWLY UPGRADED SDI+ OPTICS ENABLES A 300% IMPROVEMENT IN CONTRAST OVER SDI. METHODS/TECHNIQUES: TRANSITIONAL DISKS ARE DISKS AROUND YOUNG STARS THAT HAVE DUST-POOR GAPS. A COMMON HYPOTHESIS IS THAT MULTIPLE (2-3) MASSIVE ACCRETING PLANETS NEAR THE INNER AND OUTER EDGES OF THE WIDE GAP ARE NEEDED TO KEEP IT DUST POOR (DODSON- ROBINSON&SALYK 2011). THE PI AND HIS TEAM WILL UTILIZE MAGAO S ABSOLUTELY UNIQUE ABILITY TO TAKE H-ALPHA (656NM) AND CONTINUUM (642NM) IMAGES SIMULTANEOUSLY WITH SDI+ TO COMPLETE AND ENHANCE A SURVEY CALLED GAPPLANETS+ FOR PROTOPLANETS. SURVEY#1 (GAPPLANETS+): THE 25 NEAREST (~150 PC) YOUNGEST (~1-3 MYR) BRIGHTEST (R<12 MAG) LARGE GAP (>130MAS) TRANSITIONAL DISKS FOR THE MOST SENSITIVE SURVEY OF PROTOPLANETS IN TRANSITIONAL DISKS. SURVEY#2 (XRPROTOPLANETS+): 17 VERY CLOSE (~50-100PC) BRIGHT (I<10 MAG) YOUNG (3-10 MYR) TTAURI STARS AROUND NON-TRANSITIONAL DISKS. SCIENCE OBJECTIVES OF THE PROPOSED SURVEYS: 1. DISCOVER LOW MASS (0.5-13 MJUP) YOUNG ACCRETING EXTRASOLAR PROTOPLANETS 2. DETERMINE IF CORE-ACCRETION FORMATION THEORY IS CORRECT AND YOUNG PLANETS DO PASS THROUGH A PHASE OF RAPID GAS ACCRETION AND BRIGHT H-ALPHA FLUX (AS ALREADY OBSERVED IN LKCA 15B) 3. CHARACTERIZE THE SPATIAL DISTRIBUTION H-ALPHA LUMINOSITY ACCRETION RATES FREQUENCY AND AGES OF PROTOPLANETS AT 4-10 AU AND WIDER ORBITS 4. DETERMINE THE INFLUENCE OF PLANETS ON TRANSITIONAL DISK GAPS 5. DETERMINE IF OLDER (~3-10 MYR) NON-TRANSITIONAL DISKS ALSO HAVE DETECTABLE ACCRETING PLANETS. 6. RAPIDLY PUBLISH A PUBLIC CATALOG OF AT LEAST ~11-18 PROTOPLANET/CIRCUMPLANETARY DISK CANDIDATES AS HIGH-QUALITY TARGETS FOR JWST THERMAL FOLLOW-UP. HENCE THIS PROPOSAL IS VERY RELEVANT TO THE XRP/NASA SCIENCE PLAN AND GOALS. PROOF-OF-CONCEPT: THE LKCA 15B PLANET CAPTURED ~50% OF THE STAR S ACCRETION FLOW AND WAS ~1 000X BRIGHTER AT H-ALPHA THAN THE PREDICTED PHOTOSPHERIC H BAND FLUX FROM THE MOST OPTIMISTIC PLANET FORMATION MODELS. INDEED THE PLANET WAS NOT DETECTED AT H BAND --BUT WAS EASILY DETECTED AT H-ALPHA 120X FAINTER THAN THE STAR (AT JUST 93 MAS; 15 AU SEPARATION). HENCE IT IS CLEAR THAT SEARCHING FOR ACCRETING PLANETS AT H-ALPHA INSIDE THE GAPS OF TRANSITIONAL DISKS IS A VERY GOOD STRATEGY FOR DETECTING PROTOPLANETS AS THE CASE OF LKCA 15B PROVED.
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