PhD from Niels Bohr Institute, Copenhagen in 1991, followed by positions at UCLA, Niels Bohr Institute, Max Born Institute, Aarhus University, Jyväskylä University and Gothenburg University before taking a chair professorship at Tianjin University in 2016. I have published 200 peer reviewed papers and the monograph 'Statistical Physics of Nanoparticles in the Gas Phase’. Member of the editorial board of International Journal of Mass Spectrometry, the international advisory committee of the Electrostatic Storage Device conference series, the international advisory board of  the 26th European Conference on Few-Body Problems in Physics (Prague 2026), and co-director of several workshops held at the Majorana Centre of Scientific Culture in Erice, Sicily.

I welcome students but will not be able to take any new PhD students before retirement. 

a) The quantum supershells, prediction & discovery, b) powerlaw decays in molecular beams, c) Radiative cooling of molecules and clusters from thermally populated excited electronic states, d) fullerene coalescence, e) Modelfree determination of cluster dissociation energies, f) determination of the absolute cooling rates of C₆₀^- g) hot electron ionization.

Selected publications:
K. Hansen: The stabilization of cyanonaphthalene by fast radiative cooling,
Nature Communications 15 (2024) 8442

Shimpei Iida, et al.: Thermal radiative cooling of carbon cluster cations C_N⁺, N = 9, 11, 12, 17-27
Mon. Not. R. Astron. Soc. 514 (2022) 844–851

Jonas Wätzel et al.: Light-induced Magnetization at the Nanoscale
Phys. Rev. Lett. \textbf{128} (2022) 157205

Giovanni De Ninno, et al.: Photoelectric effect with a twist
Nature Photonics 14 (2020) 554-558

E. K. Anderson, et al.: Spontaneous Electron Emission from Hot Silver Dimer Anions: Breakdown of the Born-Oppenheimer Approximation
Phys. Rev. Lett. 124 (2020) 173001

Klavs Hansen et al.:, Single photon thermal ionization of C₆₀
Phys. Rev. Lett. 118 (2017) 103001
(PRL Editors' Suggestion)

Yuta Ebara, et al.: Detection of Recurrent Fluorescence Photons
Phys. Rev. Lett. 117 (2016) 133004

G. Ito, et al.: Cooling dynamics of photoexcited C₆^- and C₆H^-
Phys. Rev. Lett.  112 (2014) 183001

C. Leidlmair, et al.: Structures, energetics and dynamics of helium adsorbed on isolated fullerene ions
Phys. Rev. Lett. 108 (2012) 076101

A.E.K. Sundén et al.: Absolute cooling rates of freely decaying fullerenes
Phys. Rev. Lett. 103 (2009) 143001

J. Fedor, K. Hansen, J.U. Andersen, and P. Hvelplund: Nonthermal powerlaw decay of metal dimer anions
Phys. Rev. Lett. 94 (2005) 113201

S. Tomita, et al.: Dynamic Jahn-Teller effects in isolated C₆₀^- studied by near-infrared spectroscopy in a storage ring
Phys. Rev. Lett. 94 (2005) 053002

K. Hansen, et al.: Observation of 1/t decay law for hot clusters and molecules in a storage ring
Phys. Rev. Lett. 87 (2001) 123401

M. Vogel, K. Hansen, A. Herlert and L. Schweikhard: Model-free determination of dissociation energies in polyatomic systems
Phys. Rev. Lett. 87 (2001) 013401

E.E.B. Campbell, et al.: From Above Threshold Ionization to Statistical Electron Emission: The Laser Pulse Duration Dependence of C₆₀ Photoelectron Spectra
Phys. Rev. Lett.  84 (2000) 2128

C. Walther, et al.: Radiative Cooling of a Small Metal Cluster: The Case of V₁₃⁺
Phys. Rev. Lett. 83 (1999) 3816

K. Hansen and O. Echt: Reply to Comment by Stampfli and Märk
Phys. Rev. Lett. 82 (1999) 460

K. Hansen and O. Echt: Thermionic Emission and Fragmentation of C₆₀
Phys. Rev. Lett. 78 (1997) 2337

C. Yeretzian, K. Hansen and R.L. Whetten: Rates of electron emission from negatively charged, impact-heated fullerenes
Science 260 (1993) 652

C. Yeretzian, K. Hansen, F. Diederich and R.L. Whetten: Coalescence reactions of fullerenes
Nature 359 (1992) 44-47

J. Pedersen, et al.: Observation of quantum supershells in clusters of sodium atoms
Nature 353 (1991) 733

S. Bjørnholm, et al.: Mean-field quantization of several hundred electrons in sodium metal clusters
Phys. Rev. Lett. 65 (1990) 1627

K. Hansen: Statistical Physics of Nanoparticles in the Gas Phase

Springer, (2013, 2018) (1st & 2nd edition)

Complete publication list at http://www.klavshansen.cn/

1000 talents prize of Tianjin, 2016.

Atomic physics

PI on a number of beam time grants.