H. E. Swanson

Learn More
Forty years ago, Apollo astronauts placed the first of several retroreflector arrays on the lunar surface. Their continued usefulness for laser ranging might suggest that the lunar environment does not damage optical devices. However, new laser ranging data reveal that the efficiency of the three Apollo reflector arrays is now diminished by a factor of 10(More)
A next-generation lunar laser-ranging apparatus using the 3.5 m telescope at the Apache Point Observatory in southern New Mexico has begun science operation. The Apache Point Observatory Lunar Laser-ranging Operation (APOLLO) has achieved 1 mm range precision to the moon, which should lead to approximately 1 order-of-magnitude improvements in several tests(More)
A next-generation lunar laser ranging apparatus using the 3.5 m telescope at the Apache Point Observatory in southern New Mexico has begun science operation. APOLLO (the Apache Point Observatory Lunar Laser-ranging Operation) has achieved one-millimeter range precision to the moon which should lead to approximately one-order-of-magnitude improvements in(More)
Lunar laser ranging (LLR) has for decades stood at the forefront of tests of gravitational physics, including tests of the equivalence principle (EP). Current LLR results on the EP achieve a sensitivity of a/a ≈ 10 −13 based on few-centimeter data/model fidelity. A recent push in LLR, called APOLLO (the Apache Point Observatory Lunar Laser-ranging(More)
In most cases authors are permitted to post their version of the article (e.g. in Word or Tex form) to their personal website or institutional repository. Authors requiring further information regarding Elsevier's archiving and manuscript policies are encouraged to visit: a b s t r a c t In 1970, the Soviet Lunokhod 1 rover delivered a French-built laser(More)
A sensitive, systematic search for feeble, macroscopic forces arising from the exchange of hypothetical ultra-low-mass bosons was made by observing the differential acceleration of two different test body pairs toward two different sources. Our differential accelerometer — a highly symmetric, continuously rotating torsion balance — incorporated several(More)
We present the design, description, calibration procedure, and an analysis of systematic effects for an apparatus designed to measure the rotation of the plane of polarization of a transversely polarized slow neutron beam as it passes through unpolarized matter. This device is the neutron optical equivalent of a crossed polarizer/analyzer pair familiar from(More)
In the meson exchange model of weak nucleon-nucleon (NN) interactions, the exchange of virtual mesons between the nucleons is parameterized by a set of weak meson exchange amplitudes. The strengths of these amplitudes from theoretical calculations are not well known, and experimental measurements of parity-violating (PV) observables in different nuclear(More)
The positron-neutrino correlation in the 0 + → 0 + β decay of 32 Ar was measured at ISOLDE by analyzing the effect of lepton recoil on the shape of the narrow proton group following the superallowed decay. Our result is consistent with the Standard Model prediction; for vanishing Fierz interference we find a = 0.9989 ± 0.0052 ± 0.0036. Our result leads to(More)
  • 1