Alkwin Slenczka studied physics and received his doctorate under the supervision of J. Peter Toennies at the Max Planck Institut für Strömungsforschung, Göttingen. As a Feodor Lynen fellow of the Alexander von Humboldt Foundation, he joined the group of Dudley R. Herschbach at Harvard University as a post-doc. After returning to Germany, he became a research assistant at the Institute of Physical and Theoretical Chemistry at the University of Regensburg. There he habilitated and became an associate professor of Physical Chemistry. His current research deals with micro-solvation in superfluid helium nanodroplets.Jan Peter Toennies received a Ph.D. in Chemistry from Brown University, Providence USA. He then joined the Physics Department of the University of Bonn to learn about molecular beams in the group of Professor Wolfgang Paul. In 1969, he was appointed as a scientific member of the Max Planck Society and director at the Max Planck Institut (MPI) für Strömungsforschung in Göttingen.  As an emeritus, he continues his research in the successor MPI für Dynamik und Selbstorganisation. He has received numerous international awards including the Stern Gerlach Medal of the German Physical Society.

• Coulomb Explosion Imaging of Small Clusters of Helium (Maxim Kunitski).-  Mass Spectroscopy of Pure and Doped Droplets (Paul Scheier).-   Infra-red Spectroscopy (Gary Douberly).-  Electronic Spectroscopy (Alkwin Slenczka).-  Spectroscopy of Biomolecules (Gert von Helden and Eike Mucha).-  X-Ray Imaging of Droplets (Thomas Möller).- Structure of Biomolecules in Droplets (Wei Kong).-  Alignment of Molecules in Helium Droplets (Henrik Stapelfeldt).- .    Fabrication of Metal Clusters in Helium Droplets (Florian Lackner).-  Ultrafast Dynamics in Droplets (Marcel Mudrich, and Frank Stienkemeier).- Appendix: Helium Droplet Tutorial (Jan Peter Toennies).

“I can’t help but fully share the editors’ acknowledgement to all the 39 authors ‘for their stellar contributions, which will make this book a long-lasting classical reference point for both practitioners and learners’.” (Giorgio Benedek, Il Nuovo Saggiatore, Vol. 38 (3-4), 2022)