title: Constraints on spin-dependent short-range interaction between nucleons.
abstract: We search for a spin-dependent P- and T-violating nucleon-nucleon interaction mediated by light pseudoscalar bosons such as axions or axionlike particles. We employ an ultrasensitive low-field magnetometer based on the detection of free precession of colocated 3He and 129Xe nuclear spins using SQUIDs as low-noise magnetic flux detectors. The precession frequency shift in the presence of an unpolarized mass was measured to determine the coupling of pseudoscalar particles to the spin of the bound neutron. For boson masses between 2 and 500  μeV (force ranges between 3×1(-4)  m and 10(-1)  m) we improved the laboratory upper bounds by up to 4 orders of magnitude.
authors.affiliation: Institut für Physik, Johannes Gutenberg-Universität, 55099 Mainz, Germany.
authors.forename: K
authors.initials: K
authors.lastname: Tullney
authors.affiliation: Physikalisches Institut, Universität Heidelberg, 69120 Heidelberg, Germany.
authors.forename: F
authors.initials: F
authors.lastname: Allmendinger
authors.affiliation: Physikalisch-Technische Bundesanstalt Berlin, 10587 Berlin, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Burghoff
authors.affiliation: Institut für Physik, Johannes Gutenberg-Universität, 55099 Mainz, Germany.
authors.forename: W
authors.initials: W
authors.lastname: Heil
authors.affiliation: Institut für Physik, Johannes Gutenberg-Universität, 55099 Mainz, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Karpuk
authors.affiliation: Physikalisch-Technische Bundesanstalt Berlin, 10587 Berlin, Germany.
authors.forename: W
authors.initials: W
authors.lastname: Kilian
authors.affiliation: Physikalisch-Technische Bundesanstalt Berlin, 10587 Berlin, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Knappe-Grüneberg
authors.affiliation: Physikalisch-Technische Bundesanstalt Berlin, 10587 Berlin, Germany.
authors.forename: W
authors.initials: W
authors.lastname: Müller
authors.affiliation: Physikalisches Institut, Universität Heidelberg, 69120 Heidelberg, Germany.
authors.forename: U
authors.initials: U
authors.lastname: Schmidt
authors.affiliation: Physikalisch-Technische Bundesanstalt Berlin, 10587 Berlin, Germany.
authors.forename: A
authors.initials: A
authors.lastname: Schnabel
authors.affiliation: Physikalisch-Technische Bundesanstalt Berlin, 10587 Berlin, Germany.
authors.forename: F
authors.initials: F
authors.lastname: Seifert
authors.affiliation: Institut für Physik, Johannes Gutenberg-Universität, 55099 Mainz, Germany.
authors.forename: Yu
authors.initials: Y
authors.lastname: Sobolev
authors.affiliation: Physikalisch-Technische Bundesanstalt Berlin, 10587 Berlin, Germany.
authors.forename: L
authors.initials: L
authors.lastname: Trahms