Water and Organic Molecules in Protoplanetary Disks - High-R Spectroscopy - TMT science & instrument workshop Oct , Tokyo Hideko Nomura (Tokyo Tech.) Matthew J. Richter (UC Davis)
§1 Introduction
From protoplanetary disk to planets Planetisimal formation Collisional growth of planetisimals Planet formation Dispersal of gas Dust growth & settling (e.g., Hayashi et al. 1985) Observationally diagnose planet formation theory and origin of materials in our Solar System (C) Newton Press
Obs. of Gas in Protoplanetary Disks 12 CO 6-5, 3-2, 2-1, 1-0, 13 CO 3-2, 2-1, 1-0, C 18 O 2-1, 1-0, HCN, HNC, DCN, CN, CS, C 34 S, C 2 H, H 2 CO, HCO +, H 13 CO +, DCO +, N 2 H +, HC 3 N, c-C 3 H 2, etc. (sub)mm H 2 v=1-0 S(1), S(0), CO v=2, v=1, etc. H 2 Lyman-Werner band transitions Optical [OI] 6300A [OI] 63um, 145um, CO, H 2 O, CH +, HD, etc. (Herschel Space Observatory) H 2 O, OH, HCN, C 2 H 2, CO 2, NH 3 (Ground & Spitzer Space Telescope) FIR H 2 v=0-0 S(1), S(2), S(4) NIR MIR UV HCO + (4-3) ALMA SV TW Hya 100AU TMT will be able to observe IR lines with high-R & high sensitivity
Need for High-R Spectroscopy Typical width of IR lines from PPDs ~ 10-20km/s need high-R spectroscopy (R~15,000) for detection need very high-R (R~100,000) for analysing profiles Kepler rotation m m H 2 m AB Aur Gemini/TEXES (R>80,000) (Bitner et al. 2007, 2008) F~ erg/s/cm 2, v~10-20km/s
Need for High-R Spectroscopy Typical width of IR lines from PPDs ~ 10-20km/s need high-R spectroscopy (R~15,000) for detection need very high-R (R~100,000) for analysing profiles Kepler rotation See also Matt Richters poster 4.7 m CO line profiles Line emitting regions HD Subaru/IRCS (R=20,000) (Goto et al. 2006) (Pontoppidan+ 2008) VLT/CRIRES (R=100,000) SR21 Inner 11AU Inner 7AU High-R will enable us to detect fainter lines & analyse profiles of weaker lines (Y.K. Okamoto) MICHI
a Water & Organic Mol. in PPDs ESA Halley H 2 O, CO 2, CH 4, CH 3 OH, H 2 CO, NH 3, etc. §3 H2O snow line §2 formation of organic mol. Detect H2O snow lines Detect complex organic molecules with high-R TMT
§2 Formation of Organic Moleclues in PPDs
by ~ 1975 C4H- CH2OHCHO CH3CONH2 CN-C5N- C3N- NH2CH2COOH? amino acids ? Observed Interstellar Molecules Amino acids in STARDUST Amino acids in meteorites relation with interstellar molecules ? (Elsila et al. 2009) after ~ 1997
Complex Molecule Fomration on Grain Surface grain surface C, O, N, S, CO, … H \ desorption UV, CR, X-rays themal cold: < 20K warm: 30-50K Unsaturated mol. HCOOCH 3, NH 2 CHO, … NH 2, HCO, … CH 3 O grain surface (e.g., Garrod+ 2006, 2008) UV migrate CH 4, H 2 O, NH 3, H 2 S, CH 3 OH, … Saturated mol. Complex molecules are formed on grains More complex molecules on warm grains
Complex Molecules on Warm Grains Complex mol. are formed on warm grains at T~30-35K(~50A) = cometary region Z/R R [AU] Z/R R [AU] CH 3 OH C 2 H 5 OH CH 3 COCH 3 aceton T dust 30-50K (Walsh, Millar, HN et al. 2013, submitted) OSU chemical network (Harada et al. 2010, Garrod et al. 2008) Frequency [GHz] CH 3 OH line spectra Flux Density [Jy] ALMA band Strong methanol lines will be observable Methanol will be observable only at outer disk even with ALMA… Detect complex molecules & understand grain surface reactions at planet forming region with TMT!
ALMA TMT! Line flux [erg/s/cm 2 ]5e-17 Line width [km/s]20 R15,000 NELF [erg/s/cm 2 ]5e-16 S/N3 Integration time [min]15 MIR HCOOH TMT! Try first detection of MIR formic acid lines from protoplanetary disks with TMT! Z/R R [AU] HCOOH telluric
§3 H2O Snow Line
CO Snow Lines in Disks SMA 13 C 18 C 17 HD dust settling (Qi et al. 2011) CO snow R~155AU (Mathews et al. 2013) [DCO + ] /[HCO + ] =0.3 ALMA DCO ALMA cycle 0 N 2 H (Qi et al. 2013c) CO snow R~30AU TW Hya H2O snow lines around low mass stars will be difficult to access even with ALMA… Detect H2O snow lines by obs. with high-spectral TMT!
Obs. of water lines from PPDs hot MIR lines warm FIR lines cold FIR lines AA Tau Spitzer/IRS (Carr & Najita 2008) H 2 O, OH, HCN, C 2 H 2 TW Hya (Hogerheijde+ 2011) Herschel/HIFI (Riviere-Marichalar+ 2012) AA Tau Herschel/PACS [OI] H2OH2O Herschel cold m, 539 m, TW Hya, HD Spitzer hot m, TTSs: detect, HAEBEs: upper limits Herschel warm H2O TTSs, m
H2O snow lines in PPDs (Zhang+ 2013) TW Hya Spitzer/IRS Herschel Inner hole Spitzer/IRS H 2 O Snow ~4AU H 2 O Snow ~1AU (Meijerink+ 2009) model model with snow line AA Tau DR Tau AS 205 H2O line ratios + disk model predict H2O snow lines The results are model dependent… PACSHIFI
H2O Snow Line by High-R Obs. Line width ~ 10-20km/s need high-R spectroscopy (R~100,000) for analysis Kepler rotation Line flux [erg/s/cm 2 ]1e-15 Line width [km/s]20 R120,000 NELF [erg/s/cm 2 ]2e-16 S/N25 Integration time [min]20 Line Spitzer > 1e-14 erg/s/cm 2 (Carr & Najita 2011) TMT/MICHI TMT will be able to analyze statistical properties of H2O snow lines!
Summary High-R spectroscopy of transition lines of water & organic molecules in PPDs Detect H2O snow line by very high (R~100,000) spectroscopy for understanding rocky/gaseous planet forming regions Detect complex organic molecules and understand grain surface reactions in planet forming regions by high (R~15,000) spectroscopy for predicting formation of more complex molecules