Solid State Astrochemistry of Star Forming Regions


April 13 – 17, 2003



The Workshop

This workshop was organized to bring together astronomers working on observations and theoretical modelling of star forming regions, and the experimental and theoretical physical scientists working on surface reactions and processes. Over the last few years chemical physicists and physical chemists have recognized that laboratory astrophysics and its associated theoretical work have key contributions to make to problems in astronomy. Similarly, astronomers have welcomed the results and findings from laboratory astrophysics, incorporating these basic science results into their models and interpretations of observations. One major aim of this workshop was to encourage this interdisciplinary approach, and we successfully introduced many established researchers from outside the field to astrochemistry. The astronomers were also introduced to the current state-of-the art in laboratory and theoretical chemistry research on surfaces, and were given an appreciation of the limitations of current laboratory / computer technology, when applied to many of the astronomical data needs. The workshop environment also offered an excellent opportunity to address many of the language and conceptual problems that have arisen with researchers from opposite fields placing different emphases on the most significant focus of their research.


Over 60 scientists from Europe, USA and Japan attended the meeting, split around 50:50 between astronomers and physicists / chemists. Through the generosity of our sponsors, ten fully funded places were made available to young researchers, either at senior PhD or postdoctoral level, by open competition. Over 30 applications were received, and many of those who applied but were unsuccessful in receiving bursaries, later also attended the meeting. Local participants were also encouraged to attend, and around 15- 20 local attendees were present, from Leiden, Amsterdam, Eindhoven and Delft Universities. In addition a number of ‘foreign’ guests, not officially registered for the meeting, came to stay in Leiden at their own expense for the opportunity to listen to the lectures and discussions. This was a very popular and timely meeting!



The workshop highlighted four major questions that were chosen in advance of the meeting by the organizing committee, either because they were of current interest (and debate) in the literature, or are often raised / debated at other meetings, where no opportunity of discussion is possible. These were:

1.                  Data Needs and Validation

2.                  H2 Formation on Astronomically Relevant Surfaces

3.                  Ices in Star Forming Regions

4.                  Chemical reactions (not H2) on grain / ice surfaces

Each day focused on one of the topics, starting with a plenary review lecture, one hour long (including 10 minutes of questions and discussion), and followed by 4 or 5 invited lectures of 30 - 45 minutes each (also including 5 – 10 minutes of questions and discussion) highlighting the latest results in each area, from laboratory, theoretical and observational perspectives. The afternoons were wholly set-aside for discussions lead by a key researcher in the field, and open to all attendees to contribute. Attendance at these sessions was purely voluntary, although almost all participants were always present and many people made lively (and occasionally controversial) comments and suggestions during the sessions. In addition over 30 posters were exhibited throughout the week on boards along the corridor of the Lorentz Center itself. These posters were excellent: a focal point for discussions during coffee and tea breaks, lunch and of course the poster session itself.


Outcome from the Workshop

By the end of the workshop summaries of each of the discussion sessions were drawn up, highlighting to the chemists / physicists a list of major reactions, and molecules for which viable heterogeneous synthesis routes are required, the data needs surrounding these reactions and the conditions under which they might occur. Both laboratory experiments and theoretical chemistry were highlighted as key routes to understanding the astrochemistry that underpins the chemical evolution of star forming regions. Astronomers were also bombarded with some recurrent and difficult questions, with many chemists wanting to ‘pin-down’ some of the ‘facts’ surrounding the prevailing physical conditions in many of these harsh interstellar regions. In a similar vein, the astronomers were able to obtain a list of key requirements from the chemists that will help narrow the currently broad span of possible laboratory experiments, showing which laboratory results can be most suitably applied into astronomy, and stressing what limitations should be placed on the interpretation of laboratory results.


Many new collaborations have been instigated as a result of this workshop, on national and international levels. A number of scientists have been invited to visit other laboratories, and some interesting links have been forged, that would not have been possible without this meeting. It was agreed in the closing session to provide a ‘fact sheet’ of information to the whole community, so that everyone can ‘sing from the same hymn sheet’ when we are discussing physical conditions in diffuse, dense and star forming regions, and understand the units and language we are using across different fields. This sheet will most probably take the form of a short review letter, to be published shortly in the literature. In addition, the summary sheets, talks and posters have been made available in an electronic ‘proceedings’ on the internet, on the conference web page at the Lorentz Center:


The Lorentz Center

The aims of the Lorentz Center fitted beautifully with the interdisciplinary nature of this meeting. Many participants were very grateful to have an office, with access to their own room for discussions, email and quiet time to reflect on the meeting. It was also a great success to be able to accommodate so many different people from diverse research fields, ensuring astronomers and chemists were always sharing their offices with a new colleague, from the “other” field, rather than someone that was necessarily known to them before the meeting.


The facilities were well used by all the participants, with the common room filling every coffee break, and many people sitting around during lunch. With posters, and in order to accommodate such a large group, the corridor of the Center itself proved a popular meeting point, and many discussions ensued! The welcome drinks on the first evening of the meeting proved a great ice breaker, and the ideal opportunity for the two communities to mix. By the end of the week, after further drinks in the poster session, and a conference dinner, the two communities had certainly merged and developed a mutual understanding for each other. Of course all the social and scientific interactions were superbly assisted by the excellent (20o +) sunny weather that the Lorentz Center so kindly, arranged for us, which ensured every evening delegates would be found somewhere by a lonesome soul wandering the terraces of Leiden’s many cafes!! We are very grateful for the opportunity to use the Lorentz Center for this workshop.



Several organizations assisted with financial support for this workshop, particularly for the younger participants. These were:

·         Lorentz Center

·         Royal Society of Chemistry, UK, Tony and Angela Fish Bequest

·         Royal Astronomical Society, UK

·         NOVA, The Dutch Research School for Astronomy

·         The Astrophysical Chemistry Group of the RSC / RAS

·         Pfeiffer Vacuum

·         Varian

·         Hositrad Holland

·         Dutch Space

We are very grateful to all the sponsors, the staff of the Lorentz Center, Programme Board, and workshop participants, for their major contributions in making this workshop a success. The workshop was organized on behalf of the Astrophysical Chemistry Group of the RSC and RAS, UK.


H. Fraser (Leiden University, Netherlands)

I. Sims (University of Birmingham, UK)

R. Kaiser (Univ of Hawaii, USA)

J. Yates (Univ College London, United Kingdom)

A. Richards (Univ of Manchester, United Kingdom)

D. Williams (University College London, United Kingdom)