GMT2010: High-resolution Spectroscopy of Stars with GMTNIRS GMT2010 Seoul, Korea David L. Lambert McDonald Observatory The University of Texas at Austin

William Herschel ( ) Discovered the infra-red in 1800 Discovered the infra-red in 1800 “By placing one thermometer within the [solar] red rays, separated by a prism, and another beyond them, he found the temperature of the outside thermometer raised by more than that of the inside.” “By placing one thermometer within the [solar] red rays, separated by a prism, and another beyond them, he found the temperature of the outside thermometer raised by more than that of the inside.” Humphrey Davy to Davies Giddy Humphrey Davy to Davies Giddy 3 July July 1800

Introduction Certain exciting problems in stellar astrophysics demand high-resolution IR spectra for their solution. IR advantages include: Cool stars Cool stars - bright in IR - bright in IR - IR spectra “simpler” than optical - IR spectra “simpler” than optical - key signatures in IR: molecules for elemental - key signatures in IR: molecules for elemental and isotopic abundances and isotopic abundances - H - opacity minimum at 1.6 µm - H - opacity minimum at 1.6 µm - higher dust transparency - higher dust transparency Cool gas and dust Cool gas and dust - circumstellar envelopes - circumstellar envelopes - prestellar disks - prestellar disks GMTNIRS: J, H, K, L, M (  m) in a single exposure

Introduction Spectra must be paired with model atmospheres and atomic/molecular data Atomic spectroscopy: generally high-excitation Atomic spectroscopy: generally high-excitation neutral atomic lines neutral atomic lines - Quantitative lab spectroscopy limited - Quantitative lab spectroscopy limited (gf-values for LTE) (gf-values for LTE) - Expect theoretical gf-values to be fairly - Expect theoretical gf-values to be fairly reliable reliable - Astrophysical data (e.g., gf’s from Sun, - Astrophysical data (e.g., gf’s from Sun, Arcturus, etc.) Arcturus, etc.) Few resonance and low excitation lines. Few resonance and low excitation lines. Therefore - clean spectrum at low metallicity Therefore - clean spectrum at low metallicity

Molecular spectroscopy Mix of electronic and vibration-rotation transitions Mix of electronic and vibration-rotation transitions Molecular data generally good but incomplete, but there are few active centers for lab/theoretical work on astrophysical molecules Molecular data generally good but incomplete, but there are few active centers for lab/theoretical work on astrophysical molecules Incomplete: stellar column densities » laboratory possibilities (beware of extrapolation) Incomplete: stellar column densities » laboratory possibilities (beware of extrapolation) : dissociation energies? : dissociation energies? : gf-values? : gf-values? : new molecules (ZrS, TiS) : new molecules (ZrS, TiS) Can usually predict isotopic wavelength shifts Can usually predict isotopic wavelength shifts C, N, O and F including isotopes accessible (in principle) C, N, O and F including isotopes accessible (in principle) chemical evolution of stellar systems chemical evolution of stellar systems stellar evolution, esp. dredge-ups stellar evolution, esp. dredge-ups Introduction

GMTNIRS performance: Single exposure: J, H, K, L and M (  m) Single exposure: J, H, K, L and M (  m) at R = λ/∆ λ = 50,000 (JHK) or 100,000 (LM) at R = λ/∆ λ = 50,000 (JHK) or 100,000 (LM) Slit0.085 x 1.3 arc sec with pixel scale of 20 mas Slit0.085 x 1.3 arc sec with pixel scale of 20 mas Limiting magnitude Limiting magnitude

Special (unique) factors: All in one exposure CNO as tracers of dredge-ups in stars CNO as tracers of dredge-ups in stars CO  = 1 in M,  = 2 in K,  = 3 in H CN Red system in JHK OH  = 1 in L,  = 2 in H NH  = 1 in L C 2 Ballik-Ramsay and Phillips in HK (also HF in K and HCl in L) (also HF in K and HCl in L) Obtain CNO elemental and isotopic abundances Obtain CNO elemental and isotopic abundances Probe atmospheric dynamics and structure (MOLSPHERE) Probe atmospheric dynamics and structure (MOLSPHERE)

Special (unique) factors: All in one exposure HR4049, a very metal-poor 7500K giant HR4049, a very metal-poor 7500K giant in a binary with a circumbinary disk: in a binary with a circumbinary disk: [Fe/H] = -4.7, but [C, N, O / H]  0.0 [Fe/H] = -4.7, but [C, N, O / H]  0.0 Cold CO in absorption at 2.3µm Cold CO in absorption at 2.3µm Lambert, Hinkle & Luck (1988)

Special (unique) factors: All in one exposure (HR 4049 – continued) Look for CO at 4.6µm to obtain 12 C/ 13 C and 16 O/ 17 O ratios Look for CO at 4.6µm to obtain 12 C/ 13 C and 16 O/ 17 O ratios Hinkle, Brittain & Lambert (2007) C 18 O 18 CO CO H2OH2O C 17 O

Special (unique) features: Angular resolution (aperture, AO, pixel scale) Mass loss by red giant (or all) stars is very poorly understood theoretically Mass loss by red giant (or all) stars is very poorly understood theoretically and observationally. and observationally. Map circumstellar structure in CO 4.6µm lines Map circumstellar structure in CO 4.6µm lines Smith et al. (2009)

Special (unique) features: Angular resolution (aperture, AO, pixel scale) HST/WFPC 2Phoenix slit positions Smith et al. (2009, AJ, 137, 3558)

Special (unique) features: Angular resolution (aperture, AO, pixel scale) Smith et al. (2009)

Special (unique) features: Angular resolution (aperture, AO, pixel scale) Velocity-position maps Betelgeuse VY CMa KI 7699 Å CO 1 – 0 R2 4.64μm Slit 4'' from star x: 1 pixel = 1.3 km/s y: 1 pixel = 0''.27 Slit 33'' from star Plez & Lambert (2002) Smith et al. (2009)

Special (unique) features: Angular resolution (aperture, AO, pixel scale) Betelgeuse and VY CMa are SN II progenitors Betelgeuse and VY CMa are SN II progenitors Maps of circumstellar envelopes Maps of circumstellar envelopes clues to mass loss understanding clues to mass loss understanding environment in which SN II explodes environment in which SN II explodes CO has advantages over KI or NaI CO has advantages over KI or NaI GMTNIRS with JHKLM coverage will reveal complete GMTNIRS with JHKLM coverage will reveal complete circumstellar coverage (despite short slit) circumstellar coverage (despite short slit) - will provide look at innermost regions - will provide look at innermost regions - larger number of giants in its grasp - larger number of giants in its grasp

Special (unique) features: Limiting magnitude LMC, SMC, and just a little further LMC, SMC, and just a little further Dredge-up in red giants Dredge-up in red giants

Special (unique) features: Limiting magnitude Origins of Fluorine FCNO and internal mixing Smith et al. (2005) Smith et al. (2002)

Special (unique) features: Limiting magnitude K Smith et al. (2002)

Special (unique) features: Limiting magnitude Dwarf galaxies beyond the LMC at distance modulus of 18.5 Dwarf galaxies beyond the LMC at distance modulus of 18.5 Sculptor 19.5 Sculptor 19.5 Sextans 19.7 Sextans 19.7 Carina 20.0 Carina 20.0 Fornax 20.7 Fornax 20.7 Large surveys of “nearby” systems and stars Large surveys of “nearby” systems and stars - Our globular clusters - Our globular clusters - Field stars after GAIA - Field stars after GAIA CNOF chemical evolution and internal mixing CNOF chemical evolution and internal mixing

DO NOT FORGET! Glorious puzzles remain in stellar astrophysics in this age of cosmology Glorious puzzles remain in stellar astrophysics in this age of cosmology The GMT and GMTNIRS will help solve many puzzles The GMT and GMTNIRS will help solve many puzzles “Nature shows us of the lion only the tail. But there is no doubt in my mind that the lion belongs with it, even if he cannot reveal himself to the eye all at once because of his huge dimensions.” “Nature shows us of the lion only the tail. But there is no doubt in my mind that the lion belongs with it, even if he cannot reveal himself to the eye all at once because of his huge dimensions.” A. Einstein A. Einstein

Even Einstein observed!

The GMT will reveal the lions!