Photodissociation in astrochemistry
Please check back for additional details nearer the
workshop's commencement or contact Alan Heays,
Leiden Observatory is hosting a workshop on the subject of
photodissociation in astrochemistry on 3-5 February 2015 at Leiden in
This focussed workshop seeks to clarify the outstanding questions and
priorities relevant to the forthcoming era of astrochemistry, and
evaluate the present and future capabilities of spectroscopists and
chemical physicists. We hope to encourage the investigation of
photodissociation problems of immediate interest to astrochemistry.
The format of the meeting will be in the spirit of a true workshop,
with plenty of time for discussions and interactions. The number of
participants will be limited to about 40.
Venue and accomodation
The workshop will be held in Kasteel Oud Poelgeest, a beautifully
renovated castle on the border of the city of Leiden
Leiden is easily reachable by train or car from the nearby
international airport of Amsterdam Schiphol.
We have arranged for a three nights accomodation package at Poelgeest
itself for a total cost of €340, which combined with the
workshop registration includes all meals for three days.
There are also many other hotels in Leiden. For example,
are handy to the central train station.
Connections between the venue and Amsterdam/Schiphol airport
The train connection between Amsterdam/Schiphol airport and Leiden
Central Station is very good, with trains departing every 15 minutes and
the journey requiring 20 minutes.
Travelling from Leiden Central to nearby Kasteel Oud
Poelgeest is possible by bus. Good advice on public transport may be
The taxi fare between Schiphol airport and Poelgeest is around €65,
and between Leiden and Poelgeest around €10.
The workshop fee is €120 (invitees exempt) which also provides for
coffee break refreshments and lunches. There is also a sponsored workshop
dinner in the centre of Leiden on February 3, and a buffet dinner at
the venue on February 4.
Payment of the workshop fee and Poelgeest accomodation costs is due
upon departure. There is also limited support for travel and
accomodation costs upon inquiry.
Proposed topics for discussion
Problems in astrochemical photodissociation
Which molecules are present in clouds, disks, and planet atmospheres
exposed to intense UV radiation; how do they photodissociate:
through lines or continuum; how do they (observably) influence
What are the important ranges of temperature, density, extinction
magnitudes, and UV wavelengths?
What is the most useful kind of data? A completely assigned and
modelled spectrum, raw experimental cross sections and linelists,
superb accuracy over a small wavelength range (e.g., Ly alpha) or
lower accuracy over a much larger range? Importance of self- and
mutual shielding and tabulation of shielding functions; isotope
Photolysis in the gas phase vs ices; small versus large molecules
Contributions to public databases:
KIDA (KInetic Database for Astrochemistry)
Mainz UV/VIS database
Leiden photodissociation database of astrophysical molecules
Capabilities and challenges of laboratory experiments
The generation of UV radiation: synchrotrons, lasers, plasmas, or
The quantitative measurement of cross sections and dissociation:
photoabsorption, fluorescence, or the detection of dissociation
products and their excitation states; branching ratios to products.
The synthesis and study of radical species and ions, as well as ices.
- Calculation of electronic structure and dipole moments
- Nuclear dynamics of excited states, modelling the branching ratio
of ionisation, dissociation products, and fluorescence.
- More empirical theoretical models with increasing complexity:
competition between dissociation and internal conversion for