arXiv subjects

J. DiSciacca

Publications and source records attributed to J. DiSciacca.

4 recordsLinked to original sources

arXiv2013

Resolving an Individual One-Proton Spin Flip to Determine a Proton Spin State

Previous measurements with a single trapped proton or antiproton detected spin resonance from the increased scatter of frequency measurements caused by many spin flips. Here a measured correlation confirms that individual spin transitions and states are detected instead. The high fidelity suggests that it may be possible to use quantum jump spectroscopy to measure the p and \pbar magnetic moments much more precisely.

physics.atom-ph↗

arXiv2013

One-Particle Measurement of the Antiproton Magnetic Moment

\DeclareRobustCommand{\pbar}{\HepAntiParticle{p}{}{}\xspace} \DeclareRobustCommand{\p}{\HepParticle{p}{}{}\xspace} \DeclareRobustCommand{\mup}{$μ_{p}${}{}\xspace} \DeclareRobustCommand{\mupbar}{$μ_{\pbar}${}{}\xspace} \DeclareRobustCommand{\muN}{$μ_N${}{}\xspace For the first time a single trapped \pbar is used to measure the \pbar magnetic moment ${\bmμ}_{\pbar}$. The moment ${\bmμ}_{\pbar} = μ_{\pbar} {\bm S}/(\hbar/2)$ is given in terms of its spin ${\bm S}$ and the nuclear magneton (\muN) by $μ_{\pbar}/μ_N = -2.792\,845 \pm 0.000\,012$. The 4.4 parts per million (ppm) uncertainty is 680 times smaller than previously realized. Comparing to the proton moment measured using the same method and trap electrodes gives $μ_{\pbar}/μ_p = -1.000\,000 \pm 0.000\,005$ to 5 ppm, for a proton moment ${\bmμ}_{p} = μ_{p} {\bm S}/(\hbar/2)$, consistent with the prediction of the CPT theorem.

physics.atom-ph↗

arXiv2012

Direct Measurement of the Proton Magnetic Moment

The proton magnetic moment in nuclear magnetons is measured to be $μ_p/μ_N \equiv g/2 = 2.792\,846 \pm 0.000\,007$, a 2.5 ppm (parts per million) uncertainty. The direct determination, using a single proton in a Penning trap, demonstrates the first method that should work as well with an antiproton as with a proton. This opens the way to measuring the antiproton magnetic moment (whose uncertainty has essentially not been reduced for 20 years) at least $10^3$ times more precisely.

physics.atom-ph↗

arXiv2010

Self-Excitation and Feedback Cooling of an Isolated Proton

The first one-proton self-excited oscillator (SEO) and one-proton feedback cooling are demonstrated. In a Penning trap with a large magnetic gradient, the SEO frequency is resolved to the high precision needed to detect a one-proton spin flip. This is after undamped magnetron motion is sideband-cooled to a 14 mK theoretical limit, and despite random frequency shifts (larger than those from a spin flip) that take place every time sideband cooling is applied in the gradient. The observations open a possible path towards a million-fold improved comparison of the antiproton and proton magnetic moments.

physics.atom-ph↗