Spectroscopic Parameters
for the Atmospheres of
Extrasolar Planets
Laurence S. Rothman
Harvard-Smithsonian Center for Astrophysics
Atomic and Molecular Physics Division
Cambridge MA 02138, USA
Molecules in the atmospheres
of extrasolar planets
Paris, FRANCE
19-21 Novembre 2008
1
PAST
2
3
4
1824 ► Greenhouse effect
- gases in the atmosphere increase the
surface temperature of the Earth
- Planets lose energy by infrared radiation
(that Fourier called "chaleur obscure" or
"dark heat")
- Fourier transform spectroscopy (FTS)
Jean Baptiste Joseph Fourier
March 21, 1768 – May 16, 1830
5
Joseph-Marie Jacquard – 1801
Charles Babbage ~ 1820
HITRAN – 1973
Florida - 2000
6
HITRAN law?
7
PRESENT
8
96 (2005) 139-204
9
File Structure of HITRAN Compilation
Level 1
JavaHAWKS Software Installers and Documentation
HITRAN
(line-transition
parameters)
IR
Crosssections
UV
Aerosol
Refractive
Indices
Level 2
Lineby-line
Crosssections
Line
Coupling
CO2
data
Global Data
Files, Tables,
and References
Supplemental
Supplemental
Alternate
Moleculeby-molecule
Level 3
10
HITRAN Line-by-line Parameters
Parameter
Field size
Definition
Mol
I2
Molecule number
Iso
I1
Isotopologue no.(1 = most abundant, 2 = second most abundant, …)
νif
F12.6
Transition wavenumber in vacuum [cm-1]
Sif
E10.3
Intensity [cm-1/(molecule∙cm-2) @ 296K]
Aif
E10.3
Einstein A-coefficient [s-1]
γair
F5.4
Air-broadened half-width (HWHM) [cm-1/atm @ 296K]
γself
F5.4
Self-broadened half-width (HWHM) [cm-1/atm @ 296K]
E″
F10.4
Lower-state energy [cm-1]
nair
F4.2
Temperature-dependence coefficient of γair
δair
F8.6
Air pressure-induced shift [cm-1/atm @ 296K]
v′, v″
2A15
Upper and Lower “global” quanta
q′, q″
2A15
Upper and Lower “local” quanta
ierr
6I1
Uncertainty indices for νif , Sif , γair , γself , nair , δair
iref
6I2
Reference pointers for νif , Sif , γair , γself , nair , δair
*
A1
Flag for line-coupling algorithm
2F7.1
Upper and Lower statistical weights
g′, g″
160-character total
11
12
Some New Updates
H2O – water
►Reassignment of visible spectra [Tennyson et al]
► Update of γself [Gamache et al]
► Implement IUPAC results [Tennyson et al]
CO2 – carbon dioxide
► OCO line list for near IR [Brown, Miller et al]
► CDSD [Tashkun et al]
► Weak bands [Campargue et al]
CH4 – methane
► New 0 to 4800 cm-1 [Brown et al]
► CH3D 3300-3700 cm-1 [Brown et al]
► Line-shape calculations, supplemented with exp.
13
Methane Challenge
2.3 μm
new
 Global fit 
1.7 μm
14
More New Updates…..
O3 – Ozone
► Major update 1632-5870 cm-1 [Reims/Tomsk]
► Improved line-shape algorithm
O2 – Oxygen
► (UV) Corrected Schumann-Runge list
► Added Herzberg bands
► Improved A-band [Brown and co-workers]
HNO3 – nitric acid
► Update 600-1790 cm-1 [Perrin et al]
► Further Improvements in 11-µm region [Gomez et al]
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Species Currently Covered (line-by-line portion)
Molecule
# of isotopologues
Molecule
# of isotopologues
H2O
6
HCl
2
COF2
1
CO2
8
HBr
2
SF6
1
O3
5
HI
1
H2S
3
N2O
5
ClO
2
HCOOH
1
CO
6
OCS
5
HO2
1
CH4
3
H2CO
3
O
1
O2
3
HOCl
2
ClON2O
2
NO
3
N2
1
NO+
1
SO2
2
HCN
3
HOBr
2
NO2
1
CH3Cl
2
C2H4
2
NH3
2
H2O2
1
CH3OH
1
HNO3
1
C2H2
2
CH3Br
2
OH
3
C2H6
1
CH3CN
1
HF
1
PH3
1
CF4
1
Molecule
# of isotopologues
97 Isotopologues
16
Species Currently Covered (IR Cross-sections)
Molecule
Name
Molecule
Name
SF6
Sulfur hexafluoride
CHClFCF3
HCFC-124
ClON2O
Chlorine nitrate
CH3CCl2F
HCFC-141b
CCl4
Carbon Tetrachloride
CH3CClF2
HCFC-142b
N2O5
Dinitrogen pentoxide
CHCl2CF2CF3
HCFC-225ca
HNO4
Peroxynitric acid
CClF2CF2CHClF
HCFC-225cb
C2F6
CFC-116
CH2F2
HFC-32
CCl3F
CFC-11
CHF2CF3
HFC-125
CCl2F2
CFC-12
CHF2CHF2
HFC-134
CClF3
CFC-13
CFH2CF3
HFC-134a
CF4
CFC-14
CF3CH3
HFC-143a
C2Cl2F3
CFC-113
CH3CHF2
HFC-152a
C2Cl2F4
CFC-114
SF5CF3
Trifluoromethyl sulfur
pentafluoride
C2ClF5
CFC-115
CH3C(O)OONO2
PAN
CHCl2F
HCFC-21
CH3CN
Methyl cyanide
CHClF2
HCFC-22
C6H6
Benzene
CHCl2CF3
HCFC-123
17
IUPAC Water-Vapor Task
Distributed Information System
• Collect all kinds of original information
about the high-resolution spectroscopy of
the water molecule
• Provide active storage of these data
and related metadata
• Deliver information to users in different
forms via the Internet
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IUPAC vs HITRAN
Ro-vibrational levels
for H217O
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Intersection des Banques de Données
HITRAN et HITEMP
HITEMP
HITRAN
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HITRAN vs HITEMP CO2
• 250 ppm CO2
• 5-meter source
• 100 feet above the surface
HITEMP vs HITRAN CO2 1500 K
3.00E-04
2.50E-04
HITEMP
2.00E-04
1.50E-04
HITRAN
1.00E-04
5.00E-05
0.00E+00
2100
2200
2300
Wavenum ber
8.00E-04
Radiance
Radiance
HITEMP vs HITRAN CO2 1000 K
2400
HITRAN
2.00E-04
2200
2300
2400
Wavenum ber
HITEMP vs HITRAN CO2 1500 K
8.00E-06
2.00E-05
6.00E-06
HITEMP
4.00E-06
2.00E-06
HITRAN
3400
3500
3600
Wavenum ber
Radiance
Radiance
HITEMP
4.00E-04
0.00E+00
2100
HITEMP vs HITRAN CO2 1000 K
0.00E+00
3300
6.00E-04
1.50E-05
HITEMP
1.00E-05
5.00E-06
0.00E+00
3300
HITRAN
3400
3500
3600
Wavenum ber
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Comparison of CDSD and old HITEMP with Measurements
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HITEMP
• Line-absorption parameters in HITRAN format
• Constituents
- Water Vapor: 0 to 25000 cm-1 @ 1000K,1500K
- Carbon Dioxide: 400 to 10000 cm-1 @ 1000K
- Carbon Monoxide: 0 to 10000 cm-1 @ solar temperature
- Hydroxyl Radical: 0 to 19300 cm-1 @NLTE
23
New HITEMP Water List Assembly
List created using BT2 database
- for principal isotopologue, created at 296K
with lines that have significant intensity at
4000K, J <50
Partition Function
Experimental high-temperature line positions
- Based on quantum numbers, replace frequencies
with experimental ones (when available)
Convert to HITRAN2004 format
HITRAN
database
Combination of BT2, hightemperature experiments, and
HITRAN
Einstein A-coefficients,
Statistical weights
Line-shape parameters
(widths, shifts, etc)
HITEMP
Water Line List
24
Improvements and Enhancements to
the Compilation being considered
►More temperature-pressure sets of cross-sections
(IR and UV)
►Improved database structure (IUPAC paradigm)
►High-temperature parameters (HITEMP)
►Molecules for astrophysics applications
►Refined line-shape parameters
►Additional line-mixing algorithms
►Collision-Induced Absorption bands
25
Access
web site:
http://cfa.harvard.edu/HITRAN
- Gives instructions for accessing compilation (free)
- Updates
- Documentation
- Links to related databases
- HITRAN facts
- Related conferences
26
JavaHAWKS
Java version of HITRAN Atmospheric WorKStation
• Functions to manipulate and filter the HITRAN and
associated molecular spectroscopic databases
• Plotting of line-by-line files and cross-section files
• Internet access to HITRAN and other related databases
• Links to abstracts that are the sources for
HITRAN parameters
• Access to archival HITRAN documentation
27
Some Sources of Errors
in the HITRAN Database
• Theory
• Measurement
–
–
–
–
–
–
Calibration
Resolution
Photometric accuracy
Pressure, temperature, stability, …
Methods of analysis
Identification of lines
–
–
–
–
Perturbations
Line shapes
Lack of convergence
Limit of basis sets
• Units
• Transcription
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HITRAN International Advisory Committee
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SF6
CF4
(CFC-14)
CClF3
(CFC-13)
CCl2F2
(CFC-12)
Typical Cross-section files
30
Comparison of different
with high-temperature
theoretical line lists
observation
31