Chemistry, astronomy and physics of H3+

• Professor Emeritus Takeshi Oka FRS, Enrico Fermi Institute and University of Chicago, USA

Oka received his BS degree in Chemistry from the University of Tokyo in 1955 and a PhD for his work on microwave spectroscopy on formaldehyde in Professor Shimoda's lab in Physics of the same University in 1960. He was then a postdoctoral fellow at the National Research Council of Canada, later Herzberg Institute of Astrophysics. He joined the University of Chicago in 1981 jointly affiliated to the Department of Chemistry and the Department of Astronomy and Astrophysics. He joined the Enrico Fermi Institute in 1993. He became a professor emeritus in 2003.  His research interests are in the areas of high-resolution spectroscopy and astrophysics of molecular ions, in particular, H₃⁺ near the Galactic centre.  

• Professor Steven Miller, University College London, UK

Steven Miller is Professor of Science Communication and Planetary Science at University College London, where he is head of the Science and Technology Studies (STS) Department.

Professor Miller is particularly interested in the issues surrounding science and society at the European level. He is director of the European Science Communication Network and co-author of Science in Public: communication, culture and credibility .

As a planetary scientist, Professor Miller’s main interests lie in understanding how the atmospheres of giant planets – like Jupiter and Saturn, and some of the hot, giant exoplanets – couple with the space environment around them.  He has pioneered the use of infrared emission from the H₃⁺ molecular ion as a probe of planetary atmospheres.

His latest book The Chemical Cosmos: a guided tour (Springer, 2011) is a popular science “journey” through cosmo-chemistry, guided by H₃⁺. 

• Professor Mats Larsson, Stockholm University, Sweden

Mats Larsson is professor of physics at the Department of Physics, Stockholm University, and also director of the AlbaNova University Center, a joint enterprise between Stockholm University and the Royal Institute of Technology. He is member of the Royal Swedish Academy of Sciences and its physics class, which the awarding institution for the Nobel Prizes in Physics and Chemistry. He has a long affiliation with H₃⁺ and wrote the first proposal for an experiment with H₃⁺ in the storage ring CRYRING exactly 20 years ago. Needless to say, the situation concerning the recombination of H₃⁺ was also at that time in complete turmoil.

• Professor Stephan Schlemmer, Universität zu Köln, Germany

After a study of physics in Wuppertal and Göttingen Professor Schlemmer prepared a Diploma thesis (1986) and a PhD thesis (1991) in the group of Professor J P Toennies at the Max-Planck-Institute for fluid dynamics in Göttingen working on the evaporation of water from a thin liquid jet and on inelastic and reactive collisions in a crossed beam experiment. As a post-doc (1992-1994) at the University of California at Berkeley, USA, in the group of Professor R J Saykally he searched for the origin of the interstellar unidentified infrared bands (UIR) using an IR emission spectrometer. From 1994-2003 he worked in the group of Professor D Gerlich (University of Technology Chemnitz) on the trapping of ions and nanoparticles. After his habilitation he worked as an assistant professor at the University of Technology Chemnitz. During this time they developed the methods of nanoparticle mass determination and light induced reactions as a technique of ion spectroscopy. 2003 and 2004 he was appointed as an associate professor at Leiden observatory heading the group of laboratory astrophysics. Since 2004 he is professor for experimental physics at Cologne University. The work of his group focusses on spectroscopy of molecules in the THz and IR regime. In addition they are interested in understanding molecular collisions in various interstellar environments ranging from the cold universe, where eg isotopic enrichment prevails to circumstellar envelops where refractory species are produced at much higher temperatures.

• Professor Ludwik Adamowicz, University of Arizona, USA
• Audio recording (mp3)

Ludwik Adamowicz was born in Warsaw, Poland, in 1950. He received his Ph.D. degree in quantum chemistry from the Institute of Physical Chemistry, the Polish Academy of Sciences, working in the group of Andrzej Sadlej. In 1980 he joined the group of Ed McCullough at Utah State University as a postdoc to work on diatomic MCSCF method employing numerical orbitals. In 1982 he moved to the Quantum Theory Project, University of Florida, to work as a postdoc with Rodney Bartlett on various projects involving the couple-cluster (CC) method (e.g. analytical gradient, first-order correlation orbitals, CC with numerical orbitals, etc.). In 1987 he was appointed as a professor at the University of Arizona, where he has been ever since. His research interests include development of multireference CC methods, methods for very accurate, explicitly correlated, Born-Oppenheimer (BO) and non-BO calculations of small atoms and molecules, methods for describing electrical conductivity and energy transfer in large heterogeneous molecular systems (DNA), as well as studies, mostly performed in collaboration with experiment, on molecular anions, on electronic and vibrational spectra of biomolecules, and on carbon-based materials. 

• Dr Oleg Polyansky, Russian Academy of Science, Russia
• Audio recording (mp3)

Oleg Polyansky received his diploma degree in radiophysics from the Gorky State University, USSR, (1979). The same year he became a junior research fellow at the Applied Physics Institute of the Russian Academy of Science (USSR at that time). His PhD work has been done at this Institute and defended at Tomsk University in 1993. By that time he was a senior research fellow of the same institute. After receiving his PhD he won the Humboldt fellowship, which he spent with Prof. Manfred Winnewisser and Professor Per Jensen in Giessen, Germany. In 1995 he took a postdoc position at University College London with Professor Jonathan Tennyson. He spent the years 2004 to 2006 as a researcher at Ulm University, Germany, and the years up to 2008 as a visiting professor at UCL. At the moment he is a group leader and leading research fellow in his home town (now called Nizhny Novgorod) at the Applied Physics Institute, Russia.  His research interests are in the development and application of methods for the high precision calculation of the spectra of small molecules and ions, and analysis of their spectra at high excitation, including high temperatures and dissociation.

• Dr Annemieke Petrignani, Leiden Observatory, Netherlands
• Audio recording (mp3)

Annemieke Petrignani completed her Masters in Applied Physics at the Delft University in the Netherlands, and received her PhD in 2005 at the FOM Institute for Atomic and Molecular Physics in Amsterdam. During this time, she worked closely with and at the Stockholm Univeristy and the Manne Siegbahn Laboratory in Sweden, performing experiments on small atmospherically relevant ions at the ion storage ring CRYRING. In 2002, she additionally fellowed at SRI International in Menlo Park, California, to construct an ion source for the preparation of quantum-state populations to study state dependencies. From 2006 to 2010, she was scientific researcher at the Max-Planck Institute for Nuclear Physics in Heidelberg, Germany. Here she performed spectroscopy on small molecular ions in both ion traps and the storage ring TSR, focusing on astrophysically relevant ions, mainly H3+. Currently, she is a scientific researcher at the Leiden Observatory in the Netherlands. She now studies larger molecules that are relevant to astrochemistry, specifically polycyclic aromatic hydrocarbons, performing experiments in ion traps with free electron lasers at the FOM Institute Rijnhuizen (as of 2012 called DIFFER) and the Radboud University Nijmegen in the Netherlands. 

• Professor Stephan Schlemmer, Universität zu Köln, Germany
• Audio recording (mp3)

After a study of physics in Wuppertal and Göttingen Professor Schlemmer prepared a Diploma thesis (1986) and a PhD thesis (1991) in the group of Professor J P Toennies at the Max-Planck-Institute for fluid dynamics in Göttingen working on the evaporation of water from a thin liquid jet and on inelastic and reactive collisions in a crossed beam experiment. As a post-doc (1992-1994) at the University of California at Berkeley, USA, in the group of Professor R J Saykally he searched for the origin of the interstellar unidentified infrared bands (UIR) using an IR emission spectrometer. From 1994-2003 he worked in the group of Professor D Gerlich (University of Technology Chemnitz) on the trapping of ions and nanoparticles. After his habilitation he worked as an assistant professor at the University of Technology Chemnitz. During this time they developed the methods of nanoparticle mass determination and light induced reactions as a technique of ion spectroscopy. 2003 and 2004 he was appointed as an associate professor at Leiden observatory heading the group of laboratory astrophysics. Since 2004 he is professor for experimental physics at Cologne University. The work of his group focusses on spectroscopy of molecules in the THz and IR regime. In addition they are interested in understanding molecular collisions in various interstellar environments ranging from the cold universe, where eg isotopic enrichment prevails to circumstellar envelops where refractory species are produced at much higher temperatures.

• Professor Ben McCall, University of Illinois at Urbana-Champaign, USA
• Audio recording (mp3)

Professor McCall received his BS degree in Chemistry from the California Institute of Technology in 1995 and a joint PhD in Chemistry and Astronomy & Astrophysics from the University of Chicago in 2001. He was then a postdoctoral fellow at the University of California at Berkeley. He joined the University of Illinois faculty in 2004, and holds appointments in Chemistry, Astronomy, and Physics. His research interests are in the overlapping areas of high-resolution molecular spectroscopy and interstellar chemistry, with a particular focus on the role of molecular ions such as H₃⁺. 

• Dr Christian Jungen, Université de Paris-Sud, France and University College London, UK
• Audio recording (mp3)

Dr Christian Jungen was born in Basel (Switzerland).  After High-School (Gymnasium), he studied in experimental physics and gained his doctorate on a subject in high-resolution molecular electronic spectroscopy (1966). Postdoctoral positions include the National Research Council in Ottawa (Canada) in the group of Dr Gerhard Herzberg (1968-1970) and the University of British Columbia in Vancouver (Canada)  in the group of Dr Anthony Merer (1970-1972) and Research Position at the Centre National de la Recherche Scientifique (CNRS)  (1972-2008). He is a member of the Laboratoire de Photophysique Moléculaire and subsequently of the Laboratoire Aimé Cotton at the Université de Paris-Sud in Orsay (France). He was recipient of the Silver Medal of the CNRS (1987) and has had various visiting  professorships: University of British Columbia (1975-1976), University of Oxford (2000), ETH Zürich (2005-2006), University College London (2008-2012).

• Dr Holger Kreckel, MPI Kern Physik, Germany
• Audio recording (mp3)

Holger Kreckel grew up in a small town in the Westerwald, a mountain range in the middle of Germany. He attended schools in the vicinity of his home town and received the university-entrance qualification in 1992. Following 1 year of mandatory military service, Kreckel enrolled at Siegen University as a full-time physics student. After completing his Vordiplom degree, he decided to move on to Heidelberg University. For his diploma thesis, Kreckel joined the group of Prof. Andreas Wolf at the Max-Planck-Institute for Nuclear Physics (MPIK). After submission of his thesis “Coulomb Explosion Imaging of H₃⁺”, Kreckel continued to work at the heavy-ion storage ring TSR at MPIK for his graduate project. During this time he build a cryogenic ion trap for the preparation of cold H₃⁺ ions for spectroscopy and collision studies. In 2007, Kreckel moved to the United States to work with Dr. Daniel W. Savin at Columbia University in New York City. To perform the first energy-resolved anion-neutral experiments, Kreckel and his colleagues developed a novel merged-beams apparatus from scratch. In 2009, Kreckel joined Prof. Benjamin McCall's group at the University of Illinois where he worked on the development of a high-resolution ion-beam spectrometer and studies of various fundamental astrophysical collision processes. 

• Professor Mats Larsson, Stockholm University, Sweden
• Audio recording (mp3)

Mats Larsson is professor of physics at the Department of Physics, Stockholm University, and also director of the AlbaNova University Center, a joint enterprise between Stockholm University and the Royal Institute of Technology. He is member of the Royal Swedish Academy of Sciences and its physics class, which the awarding institution for the Nobel Prizes in Physics and Chemistry. He has a long affiliation with H₃⁺ and wrote the first proposal for an experiment with H₃⁺ in the storage ring CRYRING exactly 20 years ago. Needless to say, the situation concerning the recombination of H₃⁺ was also at that time in complete turmoil.

• Professor John Black, Chalmers University of Technology, Sweden
• Audio recording (mp3)

John H Black was born and educated in the USA. He has been living in Sweden since 1996, where he is Professor of Radio Astronomy in the Department of Earth and Space Sciences at Chalmers University of Technology in Gothenburg.  His research interests are concerned with atomic and molecular processes in all their astronomical manifestations. Most recently he has concentrated on observations at submillimeter wavelengths with the Herschel Space Observatory and the Atacama Large Millimeter-submillimeter Array (ALMA). As a supporter of equal opportunity for diverse techniques, he welcomes photons from all parts of the electromagnetic spectrum. 

• Dr Nick Indriolo, Johns Hopkins University, USA
• Audio recording (mp3)

Nick Indriolo was born in Akron, Ohio in 1982.  In 2005 he graduated magna cum laude from Case Western Reserve University with a BS in Astronomy.  His graduate work was done at the University of Illinois under the instruction of Benjamin J McCall, and he received a PhD in Astronomy with a specialization in Astrochemistry in 2011.  Nick is currently working for David Neufeld as an Assistant Research Scientist at Johns Hopkins University. 

• Dr Thomas R Geballe, Gemini Observatory, USA
• Audio recording (mp3)

Dr Geballe obtained a PhD in physics in 1974 under Professor Charles Townes at U C Berkeley. Following postdoctoral fellowships at Berkeley and Leiden, and a Carnegie Fellowship at Hale Observatories in Pasadena, he became a staff astronomer at the United Kingdom Infrared Telescope in 1981. He was Astronomer-in-charge, Associate Director, and Head of Operations at UKIRT from 1987 until 1998, when he joined Gemini. Among his research interests are the Galactic center, the late stages of stellar evolution, H₃⁺ as a probe of interstellar gas, the composition of interstellar dust, the surfaces, atmospheres, and aurorae of solar system objects, and brown dwarfs. 

• Dr Dariusz C (Darek) Lis, California Institute of Technology, USA
• Audio recording (mp3)

Darek Lis is a Senior Research Associate in Physics at the California Institute of Technology and Deputy Director of the Caltech Submillimeter Observatory. He obtained his PhD from the University of Massachusetts at Amherst in 1989.  His areas of expertise include submillimeter observational spectroscopic and bolometric techniques. He is a member of the NASA HIFI instrument team for the Herschel Space Observatory and has been closely involved in many Herschel guaranteed and open time programs. His research interests include volatile composition of comets; astrochemistry and molecular spectroscopy of the interstellar medium, isotopic fractionation, and deuteration; photon-dominated regions; far-infrared continuum and spectroscopic studies of star-forming regions; high-mass star formation in the Galactic center; as well as molecular gas in the high-redshift universe. He is an author or co-author of over 140 refereed journal publications. He edited two books: Submillimeter Astrophysics and Technology (ASP, 2009) and Astrochemistry: Recent Successes and Current Challenges (CUP, 2006).  

• Professor Maryvonne Gerin, LERMA, Observatoire de Paris, ENS and CNRS, France
• Audio recording (mp3)

Maryvonne Gerin is working at Observatoire de Paris on the physics and chemistry of the interstellar medium. She prepared her PhD under the direction of Professor F Combes, on galaxy dynamics. She then moved toward more observational work, making use of the millimeter and submillimeter telescopes to probe the structure and composition of the interstellar medium. As a co-I of the HIFI instrument on board of the Herschel Space Observatory, she leads the PRISMAS (Probing InterStellar Molecules with Absorption line Studies) key program dedicated to the study of the diffuse interstellar medium. As of today, her main interests are understanding the coupling of gas phase and solid phase chemistry both in photo-dissociation regions and in cold dense cores, and the properties of the diffuse interstellar medium using the PRISMAS data.

• Dr Floris van der Tak, SRON, Netherlands
• Audio recording (mp3)

Dr Floris van der Tak obtained his PhD in 2000 with Ewine van Dishoeck in Leiden, where he studied the formation of high-mass stars  and developed radiative transfer codes to analyze spectra from infrared and radio telescopes, including JCMT, OVRO, and ISO.

After a post-doctoral fellowship at the Max Planck Institut für Radioastronomie in Bonn in the group of Karl Menten, he moved to the SRON laboratory in Groningen where he is now leading a research group about the physics and chemistry of star-forming regions both within and outside our Galaxy.

Dr van der Tak is an expert on submillimeter observations, molecular excitation and radiative transfer. He leads parts of several Key Programs on ESA's Herschel space telescope and is also a Lecturer in Astrophysics at the Kapteyn Institute of the University of Groningen. 

• Dr Laurent Pagani, Observatoire de Paris & CNRS, France
• Audio recording (mp3)

Dr Pagani obtained his PhD in 1986. The topic concerned the building of an heterodyne receiver in the 1.2 mm band. Since then, he developed interest in the physics and chemistry of the interstellar medium. He keeps interest in heterodyne instrumentation, works on radiative transfer codes, gas-phase chemical codes and run numerous observations of dark clouds, prestellar cores and star forming regions. Among his achievements, he took an important role in the quest of molecular oxygen, being in the team that discovered the first source of O₂ emission, he was the first to consider the influence of ortho-H₂ on the spin state dependent chemistry of H₂D⁺ and to suggest the possibility that H₂D⁺ abundance could equal that of H₃⁺. He recently discovered and explained the coreshine phenomenon (diffraction of mid-infrared light by micron-size grains in the deep interiors of dark clouds). He is the PI of a 3 THz heterodyne experiment to fly on a stratospheric balloon, CIDRE, aimed at observing HD and OH. 

• Dr Tom Stallard, University of Leicester, UK
• Audio recording (mp3)

Tom Stallard spent the first decade of his scientific career within the Physics department of University College London, having already completed an undergraduate degree in Planetary Science within the Geology department of the same university.  During this time he worked under Professor Steve Miller, and together they make the first measurements of the ion winds within the upper atmospheres of Gas Giants.  Tom expanded upon these investigations to include a long-term, currently ongoing, series of observations of Saturn's ion winds, using the NASA InfraRed Telescope Facility, in support of the Cassini mission.  In 2007, Tom won an RCUK Academic Fellowship at the University of Leicester.  Around this time, the Cassini VIMS instrument founded the British-based VIMS-MAG collaboration team, of which Tom became the lead researcher. In his work at Leicester and through this Cassini collaboration, he has been involved in the production of significant findings from both the Cassini mission itself, from the associated ground-based observations, as well as a number of independent studies of the upper atmospheres of the Gas Giants. 

• Professor Jonathan Tennyson FRS, University College London, UK
• Audio recording (mp3)

Jonathan Tennyson gained a BA in Natural Sciences from King's College, Cambridge in 1977 and a PhD in Theoretical Chemistry from the University of Sussex in 1980. He spent a productive two years as Royal Society Western European Exchange Fellow at the University of Nijmegen in the Netherlands. In 1982 he joined the Theory Group at Daresbury Laboratory. He was appointed a New Blood lecturer at University College London in Theoretical Atomic Physics in 1985. He became Professor of Physics in 1994; took over as Head of Department in 2004 and as Massey Professor of Physics in 2005. He was elected an FRS in 2009.

 His research interests cover a range of topics on the theory of small molecules. In particular he computes spectra of these molecules (such as water and H₃⁺) and collides electrons (and occasionally positrons) with them. He is interested in the astrophysical, atmospheric and other consequences of these processes. He recently started a new project, ExoMol, aimed at calculating comprehensive line lists for models exoplanets and other hot atmospheres.