Jonathan TennysonPhysics and Astronomy,

University College London

ColumbusJune 2013

Molecular line lists for exoplanets and other atmosheres

Artist’s impression of HD189733bC. Carreau, ESA

•5 year project from May 2011

•Provide data for all molecular transitions important for

exoplanet atmospheres

•Methodology: first principles quantum mechanical

calculations, informed by experiment

J Tennyson and S.N. Yurchenko, MNRAS, 425, 21 (2012).

3Taken from Bill Borucki

2012:(nearly) every

star has planets

Transit of Venus June 8th 2004 June 5th/6th 2012

Next:10th December 2117

Radial velocity / Occultation

Period = 3.52 daysPeriod = 3.52 days

Mass = 0.69 ±0.05 MMass = 0.69 ±0.05 MJupiterJupiter

Radius = 1.35 ±0.04 RRadius = 1.35 ±0.04 RJupiter Jupiter

Density = 0.35 ±0.05 g/cmDensity = 0.35 ±0.05 g/cm33

HD 209458bHD 209458b

Beaulieu et al., 2007

Knutson et al., 2007

HD189733b: Primary transit with SpitzerHD189733b: Primary transit with Spitzer

Tinetti et al., Nature, 448, 163 (2007)

Water, different T-P

Water line list: BT2

Barber et al., 2006

Confirmation of Water,methane and hazes!

Beaulieu et al., 2007

Knutson et al., 2007

Swain et al., 2008

Pont et al., 2007

G. Tinetti (private communication, 2008)

Giovanna Tinetti, UCL

So far discovered:Water H2OMethane CH4 Carbon dioxide CO2

Carbon monoxide CO

On HD189733bwith more to come

HD189733b too hot for life

HCCH / HCN degeneracy

0.4 - 16 m R ~ 300

ESA M3 candidate missionGiovanna Tinetti (UCL) launch 2024?

Exoplanet Characterisation Observatory

Telescope Baffle

V-groove Side Sunshield

GaAs Solar Cells

Detectors

Service Module

1.5m Silicon Carbide Mirror

Frontier Problems in Exoplanet Characterization• Non-equilibrium processes in exoplanet atmospheres (Stevenson et al. 2010; Madhusudhan & Seager 2011; Moses et al. 2013) CH4, CO, NH3

• Constraints on thermal inversions in hot Jupiters (Fortney et al. 2008; Spiegel et al. 2009) TiO, VO, H2S• C/O ratios and Carbon-rich atmospheres (Fortney et al. 2008; Spiegel et al. 2009) H2O, CO, HCN, CH4, C2H2,TiH, FeH• Constraints on exoplanet formation conditions (Madhusudhan et al. 2011; Oberg et al. 2011) H2O, CO, CH4

• Atmospheres and interiors of super-Earths (Bean et al. 2011; Desert et al. 2011; Miller-Ricci Kempton et al. 2011 ) H2O, CO2

Slide courtesy of N Madhusudhan (Yale)

Primordial (Metal-poor)

Terrestrial Planets (Oxidising)

Giant-Planets & Cool Stars (Reducing atmospheres)

Already available

H2, LiHHeH+, H3

+

H2D+

OH, CO2, O3, NOH2O, HDO, NH3

H2, CN, CH, CO, CO2, TiOHCN/HNC, H2O, NH3,

ExoMol O2, CH4, SO2, SO3

HOOH, H2CO, HNO3

CH4, PH3, C2, C3, HCCH, H2S, C2H6, C3H8, VO, O2, AlO, MgO,

CrH, MgH, FeH, CaH, AlH, SiH, TiH, NiH, BeH, YO

Molecular line lists for exoplanet & other atmospheres

Available from elsewhereAlready calculated at UCLWill be calculated during the ExoMol project

list of molecules

www.exomol.comFull details:J. Tennyson and S.N. Yurchenko, MNRAS, 425, 21 (2012)

,

Why theory, not experiment?

Exoplanets

Absorption (T=300K) spectrum of NH3: Accuracy

Experiment

Theory

Absorption (T=300K) spectrum of NH3: Accuracy

Experiment

Theory

Absorption (T=300K) spectrum of NH3: Accuracy

Absorption (T=300K) spectrum of NH3: Accuracy

Theory

0 2000 4000 6000 8000106104102100

wavenumber / cm-1

TROVE

Inte

nsity

/ [c

m /

mol

]

HITRAN

10-1101103105

Completeness: Absorption of ammonia (T=300 K)

Less than 30,000 NH3 lines known experimentally: BYTe contains 1.1 billion lines, about 40,000 times as many!

BYTe

S.N. Yurchenko, R.J. Barber & J. Tennyson, Mon. Not. R. astr. Soc., 413, 1828 (2011)

1 2 3 4 5 6 7 8 9 100.01

0.1

1

10

100

1000

10000

100000

1000000

Inte

nsi

ty /

[cm

/mo

le]

wave length / m

1500K 1200K 900K 600K 300K

Absorption spectra of 14NH3: Temperature effect

hc

Ne

TQ

eSI AkThc

kTE

3)4(

~8]1[

)()if()if(

0

if3

/~/

if

i

Ab initio calculations Ab initio calculations

DMS PES

Variational calculations

Rovibrational wavefunctions

Rovibrational energies

Intensities (Einstein Aif)

Line list

Refinement

Method: Spectrum from the “first-principles”

Shayesteh et al 2007

MOLPRO

Line list: MgH

Potential energy curve Dipole moment curve

Line list: 6690 lines, Nmax=60

Solve for the motion of the nuclei

MOLPRO

REFINED

Ab initio: solve for motion of electrons

B Yadin et al, MNRAS 425, 34 (2012)

LEVEL 8.0R. Le Roy, Waterloo, Canada

2 4 6 8 1010-3010-2910-2810-2710-2610-2510-2410-2310-2210-2110-2010-1910-1810-17

Inte

nsi

ty

cm/m

ol

wavelength / m

Line list (in progress): C2

Solve for the motion of the nuclei

New program duoSergei Yurchenko

1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5

-0.4

-0.2

0.0

0.2

0.4

0.6

0.8

1.0

1.2

Tra

nsi

tion

mo

me

nts

/ D

R / A

Mulliken Swan Ballik-Ramsay duck Phillips Bernath B Bernath B'

Line list:

being computed …

Potential energy Dipole moment

MOLPROMOLPRO

T. W. Schmidt et al 2011

Istvan Szabo

REFINED

Sakellaris, et al. J. Chem. Phys. 134, 234308 (2011)

FeO

Not being attempted !

Dipole moment

TROVE: Yurchenko, Thiel, Jensen

300 K line list, Clara Sousa-Silva PH3

Potential energy

Tunnelingmotion

neglected

Solve for the motion of the nuclei Line list:

T=300 K ~ 14 M transitonsHot: will be > billion

TROVE

HITRANJPL

Ab initio PES [CCSD(T)/aug-cc-pV(Q+d)Z]

Refined using lab spectra

R. I. Ovsyannikov et al. J. Chem. Phys 129, 044309 (2008).

Ab initio:CCSD(T)/aug-cc-pVTZ

S.N. Yurchenko et al. J. Mol. Spectrosc 239, 71 (2006).

TROVE

JPL HITRAN

First principles Predictions of

tunnelling beinginvestigated

1x10-30

1x10-28

1x10-26

1x10-24

1x10-22

1x10-20

1x10-20

1x10-22

1x10-24

1x10-26

1x10-28

1x10-30

1 2 3 4 5 6 7 8 9 10

HITRAN

wavelength, m

Inte

nsi

ty (

cm/m

ole

cule

)

ExoMol

Dipole moment

TROVEYurchenko, Thiel, Jensen

CH4

9D surface130 000

geometries

Potential energy

Ab initio10 electrons

Ground electronic state

Three 9D surfaces 130 000

geometries

Solve for the motion of the nuclei

Line list:

Billions of transitions

MOLPROCCSD(T)-f12/QZ

MOLPROCCSD(T)-f12/QZ

Ab initio: solve for motion of electrons

Sergei Yurchenko

1x10-30

1x10-28

1x10-26

1x10-24

1x10-22

1x10-20

1x10-20

1x10-22

1x10-24

1x10-26

1x10-28

1x10-30

1 2 3 4 5 6 7 8 9 10

HITRAN

wavelength, m

Inte

nsi

ty (

cm/m

ole

cule

)

ExoMol

Line list for warm Methane (T>600 K, J34) : line positions, Einstein coefficients, lower state energies,

quantum numbers

T=300K212,000 lines

323,720,766 lines

0

5x10-20

1x10-19

2x10-19

2x10-19

1x10-19

5x10-20

0

7 7.5 8 8.5

HITRAN

wavelength, m

Inte

nsi

ty (

cm/m

ole

cule

)

ExoMol

Absorption of Methane (T=300 K)

Albert et al., JCP 2008

0

5x10-20

1x10-19

2x10-19

2x10-19

3x10-19

3x10-19

3x10-19

3x10-19

2x10-19

2x10-19

1x10-19

5x10-20

0

3 3.1 3.2 3.3 3.4 3.5 3.6 3.7 3.8

HITRAN

wavelength, m

Inte

nsi

ty (

cm/m

ole

cule

)

ExoMol

Absorption of Methane (T=300 K)

Albert et al., JCP 20083

0

2x10-25

4x10-25

6x10-25

8x10-25

1x10-24

G.S.

1x10-24

8x10-25

6x10-25

4x10-25

2x10-25

0

0 100 200 300 400

HITRAN

wavenumber, 1/cm

Inte

nsi

ty (

cm/m

ole

cule

)

ExoMol

THz absorption of Methane (T=300 K)

1 101E-30

1E-28

1E-26

1E-24

1E-22

1E-20

1E-18

inte

nsi

ty, c

m/m

ole

cule

wavelength, m

1000K 600K 300K

hc

Ne

TQ

eSI AkThc

kTE

3)4(

~8]1[

)()if()if(

0

if3

/~/

if

i

Absorption spectra of CH4: Temperature effect

H2COT = 296 K

Ahmed Al-Refaie

• 50,000 processor hours.

• Wavefunctions > 0.8 terabites

• 221,100 energy levels (all to J=50, E = 30,000 cm) 14,889 experimentally known

• 506 Million transitions (PS list has 308M) >100,000 experimentally known with intensities

Partition function 99.9915% of Vidler & Tennyson’s value at 3,000K

BT2 linelistBarber et al, MNRAS 368, 1087 (2006).

http://www.tampa.phys.ucl.ac.uk/ftp/astrodata/water/BT2/

Obs: A. Coppalle & P. Vervisch,JQSRT, 35, 121 (1986)

New edition of HITEMP: LS Rothman, IE Gordon, RJ Barber, H Dothe, RR Gamache, A Goldman, VI Perevalov, SA Tashkun + J Tennyson, JQSRT, 111, 2139 (2010).

BT2 linelist used to to detect/model water

Nova-like V838 Mon Cometary coma

Atmosphere of Venus Exoplanets (4 so far!)Brown and M-dwarfs

As well as.....

Water concentrations in explosions

Design of high-T gas sensors

Remote detection of forest fires

Imaging gas turbine engines

Temperature profile in flames

Atmospheric models

Primordial (Metal-poor)

Terrestrial Planets (Oxidising)

Giant-Planets & Cool Stars (Reducing atmospheres)

Already available

H2, LiHHeH+, H3

+

H2D+

OH, CO2, O3, NOH2O, HDO, NH3

H2, CN, CH, CO, CO2, TiOHCN/HNC, H2O, NH3,

ExoMol O2, CH4, SO2, SO3

HOOH, H2CO, HNO3

CH4, PH3, C2, C3, HCCH, H2S, C2H6, C3H8, VO, O2, AlO, MgO, CrH, MgH, FeH, CaH, AlH, SiH, TiH, NiH, BeH, YO

Molecular line lists for exoplanet & other atmospheres

list of molecules

www.exomol.comFull details:J. Tennyson and S.N. Yurchenko, MNRAS, 425, 21 (2012)

Primordial (Metal-poor)

Terrestrial Planets (Oxidising)

Giant-Planets & Cool Stars (Reducing atmospheres)

Already available

H2, LiHHeH+, H3

+

H2D+

OH, CO2, O3, NOH2O, HDO, NH3

H2, CN, CH, CO, CO2, TiOHCN/HNC, H2O, NH3,

ExoMolIn progress

Requested

O2, CH4, SO2, SO3

HOOH, H2CO, HNO3

CH4, PH3, C2, C3, HCCH, H2S, C2H4, C2H6, VO, O2, AlO, MgO, CrH, MgH, FeH, CaH, AlH, SiH, TiH, NiH, BeH, YO

Molecular line lists for exoplanet & other atmospheres

list of molecules

www.exomol.comFull details:J. Tennyson and S.N. Yurchenko, MNRAS, 425, 21 (2012)

NaH, HF, HCl

SiO, CS, NaCl, KCl

H2S

HNO3

C3CrH

crosssections

AlONiHVO

CH4 SO3

HOOHPH3

C2H4

CH2O

MSc students: SiO, CS, NaCl, KCllCitizen scientist: AlH

H2S

HNO3

C3CrH

crosssections

AlONiHVO

CH4 SO3

HOOHPH3

C2H4

CH2O

www.exomol.com

Ala’a Azzam

Sergei Yurchenko

Dan Underwood

Oleg Polyansky

Clara Sousa-SilvaAnatoly

Pavlyuchko

Renia Diamantopoulou

Christian Hill

Maire Gorman

AndreyYachmenev

Andrei Patrascu

Lorenzo Lodi

Ahmed Al-Refaie

www.worldscibooks.com/physics/7574.html

About the first edition“The best book for anyone who is embarking on research in astronomical spectroscopy”Contemporary Physics (2006)

Published 2011

Cool atmospheres: dominated by molecular absorption

Brown Dwarfs

M-dwarf

The molecular opacity problem

Exoplanets?

M Dwarf

Planet

Marley & Leggett (2008)

Cool stars: T = 2000 – 4000 KThermodynamics equilibrium, 3-body chemistry

C and O combine rapidly to form CO.

M-Dwarfs: Oxygen rich, n(O) > n(C)H2, H2O, TiO, ZrO, etc also grains at lower T

C-stars: Carbon rich, n(C) > n(O) H2, CH4, HCN, C3, HCCH, CS, C2, CN, etc

S-Dwarfs: n(O) = n(C) Rare. H2, FeH, MgH, no polyatomics

Also (primordeal) ‘metal-free’ starsH, H2, He, H, H3

+ only at low T

Sub-stellar objects:CO less important

L-Dwarfs: T ~ 1500 K H2, H2O, CH4

T-Dwarfs: T ~ 1000 K ‘methane stars’

Y-Dwarfs: T ~ 500 K ammonia signature

Exoplanets: hot Jupiters super-Earths

How common are these objects?Deuterium burning test using HDO?

Burn D only

No nuclear synthesis