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C. Cheng, A.P.P. van der Poel, P. Jansen, M. Quintero-Pérez, T.E. Wall, W. Ubachs, and H.L. Bethlem
Molecular fountain.
Phys. Rev. Lett. 117, 253201 (2016).
(See arXiv)

C. Meng, A.P.P. van der Poel, C. Cheng and H.L. Bethlem
Femtosecond laser detection of Stark-decelerated and trapped methylfluoride molecules.
Phys. Rev. A 92, 023404 (2016).

A.P.P. van der Poel, K. Dulitz, T.P. Softley and H.L. Bethlem
A compact design for a magnetic synchrotron to store beams of hydrogen atoms.
New J. Phys. 17, 055012 (10 pages) (2015).
(See arXiv)

N. Kanekar, W. Ubachs, K. M. Menten, J. Bagdonaite, A. Brunthaler, C. Henkel, S. Muller, H.L. Bethlem, and M. Daprá
Constraints on changes in the proton-electron mass ratio using methanol lines.
Mon. Not. Royal Astr. Soc. 448, L104-L108 (2015).
(See arXiv)

A.J. de Nijs, W. Ubachs and H.L. Bethlem
Ramsey-type microwave spectroscopy on CO (a3Π)
J. Mol. Spec. 300, 79-85 (2014).
(See arXiv)

M. Quintero-Pérez, T.E. Wall, S. Hoekstra and H.L. Bethlem
Preparation of an ultra-cold sample of ammonia molecules for precision measurements
J. Mol. Spec. 300, 112-115 (2014).
(See arXiv)

J.E. van den Berg, S.C. Mathavan, C. Meinema, J. Nauta, T.H. Nijbroek, K. Jungmann, H.L. Bethlem, and S. Hoekstra
Traveling-wave deceleration of SrF molecules
J. Mol. Spec. 300, 22-25 (2014).
(See arXiv)

P. Jansen, H.L. Bethlem and W. Ubachs
Perspective: Tipping the scales: Search for drifting constants from molecular spectra.
J. Chem. Phys 140, 010901 (13 pages) (2014).
(See arXiv)

J. Bagdonaite, M. Daprá, P. Jansen, H.L. Bethlem, W. Ubachs, S. Muller, C. Henkel and K. M. Menten
Robust Constraint on a Drifting Proton-to-Electron Mass Ratio at z=0.89 from Methanol Observation at Three Radio Telescopes.
Phys. Rev. Lett. 111, 231101 (5 pages) (2013).

P.C. Zieger, C.J. Eyles, S.Y.T. van de Meerakker, A.J.A. van Roij, H.L. Bethlem and G. Meijer
A Forty-Segment Molecular Synchrotron.
Z. Phys. Chem 227, 1605-1645 (2013).

A.J. de Nijs, D. Zhao, H.L. Bethlem, H. Linnartz and W. Ubachs
Testing the mass-scaling relations in the a3Π state of 12C18O and 13C16O.
J. Mol. Spec. 292, 20-22 (2013).

P. Jansen, M. Quintero-Pérez, T.E. Wall, J.E. van den Berg, S. Hoekstra and H.L. Bethlem
Deceleration and trapping of ammonia molecules in a traveling-wave decelerator.
Phys. Rev. A 88, 043424 (8 pages) (2013).

P. Jansen, I. Kleiner, C. Meng, R.M. Lees, M.H.M. Janssen, W. Ubachs and H.L. Bethlem
Prospects for high-resolution microwave spectroscopy of methanol in a Stark-deflected molecular beam.
Mol. Phys. 111, 1923-1930 (2013).

P. Jansen, L.-H. Xu, I. Kleiner, H.L. Bethlem and W. Ubachs
Methyl mercaptan (CH3SH) as a probe for variation of the proton-to-electron mass ratio.
Phys. Rev. A 87, 052509 (5 pages) (2013).

P.C. Zieger, C.J. Eyles, G. Meijer and H.L. Bethlem
Resonant excitation of trapped molecules in a molecular synchrotron.
Phys. Rev. A 87, 0434251 (5 pages) (2013).

M. Quintero-Pérez, P. Jansen, T.E. Wall, J.E. van den Berg, S. Hoekstra and H.L. Bethlem
Static Trapping of Polar Molecules in a Traveling Wave Decelerator.
Phys. Rev. Lett. 110, 133003 (4 pages) (2013).

J. Bagdonaite, P. Jansen, C. Henkel, H.L. Bethlem, K.M. Menten and W. Ubachs
A Stringent Limit on a Drifting Proton-to-Electron Mass Ratio from Alcohol in the Early Universe.
Science 339, 46-48 (2013).

S.Y.T. van de Meerakker, H.L. Bethlem, N. Vanhaecke and G. Meijer
Manipulation and control of molecular beams.
Chem. Rev. 112, 4828-4878 (2012).

A.J. de Nijs, W. Ubachs and H.L. Bethlem
Sensitivity of rotational transitions in CH and CD to a possible variation of fundamental constants.
Phys. Rev. A 86, 032501 (6 pages) (2012).

M. Quintero-Pérez, P. Jansen and H.L. Bethlem
Velocity map imaging of a slow beam of ammonia molecules inside a quadrupole guide.
Phys. Chem. Chem. Phys. 14, 9630-9635 (2012).

V.V. Ilyushin, P. Jansen, M.G. Kozlov, S.A. Levshakov, I. Kleiner, W. Ubachs and H.L. Bethlem
Sensitivity to a possible possible variation of the proton-to-electron mass ratio of torsion-wagging-rotation transitions in methylamine CH3NH2.
Phys. Rev. A 85, 032505 (10 pages) (2012).

P. Jansen, I. Kleiner, L.-H. Xu, W. Ubachs and H.L. Bethlem
Sensitivity of transitions in internal rotor molecules to a possible variation of the proton-to-electron mass ratio.
Phys. Rev. A 84, 062505 (12 pages) (2011.)

A.J. de Nijs, E.J. Salumbides, K.S.E. Eikema, W. Ubachs and H.L. Bethlem
UV frequency metrology on CO (a3Π); Isotope effects and sensitivity to a variation of the proton-to-electron mass ratio.
Phys. Rev. A 84, 052509 (12 pages) (2011).

A.J. de Nijs and H.L. Bethlem
On deflection fields, weak-focusing and strong-focusing storage rings for polar molecules.
Phys. Chem. Chem. Phys. 13, 19052-19058 (2011).

P. Jansen, L.-H. Xu, I. Kleiner, W. Ubachs and H.L. Bethlem
Methanol as a sensitive probe for spatial and temporal variations of the proton-to-electron mass ratio.
Phys. Rev. Lett. 106, 100801 (4 pages) (2011).

P.C. Zieger, S.Y.T. van de Meerakker, C.E. Heiner, H.L. Bethlem, A.J.A. van Roij and G. Meijer
Multiple Packets of Neutral Molecules Revolving for over a Mile.
Phys. Rev. Lett. 105, 173001 (4 pages) (2010).

H.L. Bethlem and W. Ubachs
Testing the time-invariance of fundamental constants using microwave spectroscopy on cold diatomic radicals.
Faraday Discussions 142, 25-36 (2009).

C.E.Heiner, H.L. Bethlem and G. Meijer
A synchrotron for neutral molecules.
Chemical Physics Letters 473, 1-9 (2009).

H.L. Bethlem, M. Kajita, B. Sartakov, G. Meijer and W. Ubachs
Prospects for precision measurements on ammonia molecules in a fountain.
The European Physical Journal Special Topics 163, 55-69 (2008).

H.L. Bethlem
Getting a handle on difficult atoms.
Physics 1, 25 (2008).

C.E. Heiner, G. Meijer and H.L. Bethlem
Motional resonances in a molecular synchrotron.
Physical Review A 78, 030702 (4 pages) (2008).

S.Y.T. van de Meerakker, H.L. Bethlem and G. Meijer
Taming molecular beams.
Nature Physics 4, 595-602 (2008).

S.A. Meek, H.L. Bethlem, H. Conrad and G. Meijer
Trapping molecules on a Chip in Traveling Potential Wells.
Physical Review Letters 100, 153003 (4 pages) (2008).

M. Schnell, P. Lützow, J. van Veldhoven, H.L. Bethlem, J. Küpper, B. Friedrich, M. Schleier-Smith, H. Haak and G. Meijer
A Linear AC Trap for Polar Molecules in Their Ground State.
The Journal of Physical Chemistry A 111, 31, 7411-7419 (2007).

C.E. Heiner, D. Carty, G. Meijer and H.L. Bethlem
A Molecular Synchrotron.
Nature Physics 3, 115-118 (2007).

H.L. Bethlem, J. van Veldhoven, M. Schnell and G. Meijer
Trapping polar molecules in an ac trap.
Physical Review A, 74, 063403 (15 pages) (2006).

H.L. Bethlem, M.R. Tarbutt, J. Küpper, D. Carty, K. Wohlfart, E.A. Hinds and G. Meijer
Alternating gradient focusing and deceleration of polar molecules.
Journal of Physics B 39, R263-R291 (2006)

C.E. Heiner, H.L. Bethlem and G. Meijer
Molecular beams with a tunable velocity.
Physical Chemistry Chemical Physics 8, 2666-2676 (2006).

J. van Veldhoven, H.L. Bethlem, M. Schnell and G. Meijer
Versatile electrostatic trap.
Physical Review A 73, 063408 (7 pages)(2006).

S.Y.T. van de Meerakker, N. Vanhaecke, H.L. Bethlem and G. Meijer,
Transverse stability in a Stark decelerator.
Physical Review A 73, 023401 (13 pages) (2006).

F.M.H. Crompvoets, H.L. Bethlem and G. Meijer,
A storage ring for neutral molecules.
Advances in Atomic, Molecular, and Optical Physics 52. (Eds. Paul R. Berman, Chun D. Lin.) Elsevier Academic Press, Amsterdam (2006) 209-287.

S.Y.T. van de Meerakker, N. Vanhaecke, H.L. Bethlem and G. Meijer,
Higher-order resonances in a Stark decelerator.
Physical Review A 71,053409 (14 pages) (2005) .

J. van Veldhoven, H.L. Bethlem and G. Meijer,
ac Electric trap for ground-state molecules.
Physical Review Letters 94, 083001 (4 pages) (2005).

J. van Veldhoven, J. Küpper, H.L. Bethlem, B. Sartakov, A.J.A. van Roij and G. Meijer,
Decelerated molecular beams for high-resolution spectroscopy: the hyperfine structure of 15ND3.
The European Physical Journal D 31, 337-349 (2004).

S.A. Schulz, H.L. Bethlem, J. van Veldhoven, J. Küpper, H. Conrad and G. Meijer,
Microstructured Switchable Mirror for Polar Molecules.
Physical Review Letters 93, 020406 (4 pages) (2004).

F.M.H. Crompvoets, H.L. Bethlem, J. Küpper, A.J.A. van Roij and G. Meijer,
Dynamics of neutral molecules stored in a ring.
Physical Review A 69, 063406 (5 pages) (2004).

M.R. Tarbutt, H.L. Bethlem, J.J. Hudson, V.L. Ryabov, V.A. Ryzhov, B.E. Sauer, G. Meijer and E.A. Hinds,
Slowing heavy, ground-state molecules using an alternating gradient decelerator.
Physical Review Letters 92, 173002 (4 pages) (2004).

H.L. Bethlem and G. Meijer,
Production and application of translationally cold molecules.
International Review in Physical Chemistry 22, 73-128 (2003).

F.M.H. Crompvoets, R.T Jongma, H.L. Bethlem, A.J.A. van Roij and G. Meijer,
Longitudinal focusing and cooling of a molecular beam.
Physical Review Letters 89, 093004 (4 pages) (2002).

H.L. Bethlem, F.M.H. Crompvoets, R.T. Jongma, S.Y.T. van de Meerakker and G. Meijer,
Deceleration and trapping of ammonia using time-varying electric fields
Physical Review A 65, 053416 (20 pages) (2002).

H.L. Bethlem, A.J.A. van Roij, R.T. Jongma and G. Meijer,
Alternate gradient focusing and deceleration of a molecular beam.
Physical Review Letters 88, 133003 (4 pages) (2002).

S.Y.T. van de Meerakker, R.T. Jongma, H.L. Bethlem and G. Meijer,
Accumulating NH radicals in a magnetic trap.
Physical Review A 64, 041401(R) (4 pages) (2001) .

M.C. van Beek, G. Berden, H.L. Bethlem and J.J. Meulen
Molecular reorientation in collisions of OH + Ar.
Physical Review Letters 86, 4001-4004 (2001).

F.M.H. Crompvoets, H.L. Bethlem, R.T. Jongma and G. Meijer,
A prototype storage ring for neutral molecules
Nature 411, 174-176 (2001).

H.L. Bethlem, G. Berden, F.M.H. Crompvoets, R.T. Jongma, A.J.A. van Roij and G. Meijer,
Electrostatic trapping of ammonia molecules.
Nature 406, 491-494 (2000).

H.L. Bethlem, G. Berden, A.J.A. van Roij, F.M.H. Crompvoets and G. Meijer,
Trapping neutral molecules in a traveling potential well.
Physical Review Letters 84, 5744-5747 (2000).

H.L. Bethlem, G. Berden and G. Meijer,
Decelerating neutral dipolar molecules.
Physical Review Letters 83, 1558-1561 (1999).



Theses


C. Meng,
Femtosecond laser detection of xenon and Stark decelerated polyatomic molecules.
VU University (2015).

M. Quintero-Pérez,
Preparation of an ultra-cold sample of ammonia molecules for precision measurements.
VU University (2014).

A.J. de Nijs,
Molecular radicals in the search for drifting constants.
VU University (2014).

P. Jansen,
Polyatomic molecules for probing a possible variation of the proton-to-electron mass ratio.
VU University (2013).

P.C. Zieger,
A Synchrotron for Polar Molecules.
Radboud Universiteit Nijmegen (2012).

C.E. Heiner,
A Molecular Synchrotron.
Radboud Universiteit Nijmegen (2009).

J. van Veldhoven,
AC trapping and High-resolution Spectroscopy of Ammonia Molecules.
Radboud Universiteit Nijmegen (2006).

H.L. Bethlem,
Deceleration and trapping polar molecules using time-varying electric fields.
Katholieke Universiteit Nijmegen (2002).




Section Atomic, Molecular and Laser Physics - Vrije Universiteit Amsterdam
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