a dynamic database of (currently 534834 2010-jun-18) molecular model spectra for astronomers jan...
Post on 22-Dec-2015
217 views
TRANSCRIPT
A dynamic database of(currently 534834 2010-Jun-18)
molecular model spectra for astronomers
Jan CamiAndrew Markwick
1000–0110 and 1110 − 0220
Same thing at ~ same time
<< data analysis >>
(Identify molecular species)Find & understand (!) line list
Astronomical model: parameters?Radiative Transfer
Convolve with instrumental profile
Fit spectrum: determine parameters
g Her
BU And
Mira
Modeling results
Optically thin Optically thick
HR 4049 : CO2
Grains in meteorite
• In astronomy, finding parameters to within an order of magnitude is often good enough (models often necessarily simplified) !
• Sometimes we don’t really care about the parameters – we just want to know the spectral signature.
• Applicable to many different astronomical observations!
The goal:
To help people to:i)identify features in spectraii) obtain first order estimates of temperature and column density from those features
perfectblack box
All possible molecular species What’s available
All possible transitions What’s available
Full non-LTE radiative transfer Isotherm, LTE
Various geometries Slab
All possible instruments On request
sf
<< View >>Search
CompareDownloadRequest
View<< Search >>
CompareDownloadRequest
ViewSearch
<< Compare >>DownloadRequest
ViewSearch
<< Compare >>DownloadRequest
ViewSearch
Compare<< Download >>
Request
** in the download you also get the emission spectrum!
ViewSearch
CompareDownload
<< Request >>
39 molecules, 96 isotopologues
69 temperatures (10 – 2500 K)
101 column densities (1014 – 1024 cm-2)
10 instrument profiles ( = spectral resolutions)
534834 spectra, 0.3 – 3000 micron (100 GHz – 1 PHz)
Spitzer-IRS LowRes1, LowRes2, HiResISO-SWS AOT1, speed1; IRTF-SpeXVLT-ISAAC LW MedRes, VLT-CRIRESHerschel-SPIRE, Herschel-PACSGemini-Phoenix
10 instrument profiles ( ~ spectral resolutions)
Spitzer-IRS LowRes1 90Spitzer-IRS LowRes2 120Spitzer-IRS HiRes 600ISO-SWS AOT1, speed1 300IRTF-SpeX 2000VLT-ISAAC LW MedRes 10000VLT-CRIRES 100000Herschel-SPIRE 1000Herschel-PACS 1500Gemini-Phoenix 65000
Of course, none of this is possible without the line lists
3,584,261 HITRAN04/08 (Rothman et al.) multiple
3,147,603 CDSD (Tashkun et al.) CO2
279,028,856 Partridge & Schwenke H2O
~100m Schwenke TiO
39,900 Goldman et al. OH
134,421 Goorvitch CO
93,372 Langhoff & Bauschlicher SiO
31,590 Cami, Bauschlicher, Markwick et al. SiS
~ 142 molecules detected in space ~ 212 including isotopologues
42 molecules studied in earth atmosphereline lists available at 296 K (HITRAN)
often infrared
7 molecules with “warm” line lists (that we have)H2O, OH, TiO, SiO, SiS, CO, CO2
Large frequency range
Many levels (electronic, vibrational, rotational)
High temperatures
63
Carbon star chemistry
Astronomers wish list:
- More species (carbon)!
- Higher temperatures/weak lines?
- Partition functions!