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The primary project goal/objective is to demonstrate the linear motor reciprocating compressor (L... more The primary project goal/objective is to demonstrate the linear motor reciprocating compressor (LMRC) by integrating individually developed technology readiness Level 4 or higher components and to demonstrate that the compressor has improved compression efficiency and a reduced capital and maintenance cost compared to conventional reciprocating compression technology. Another project goal is to meet the flow and pressure requirements in the Multi-Year Research, Development, and Demonstration (MYRDD) Plan tables. The success of these goals will be measured based on the metrics below.
Intense Positron Beams …, 1988
Radiation pressure from lasers has been used to cool and compress 9Be+ ions stored in a combinati... more Radiation pressure from lasers has been used to cool and compress 9Be+ ions stored in a combination of static electric and magnetic fields (Penning trap) to tem eratures less than 10 mK and densities greater than lo7 cm-q in a magnetic field of 1.4 T. A technique called sympathetic cooling can be used to transfer this cooling and compression to other ion species. ions sympathetically cooled by laser cooled 9Be+ ions is given. source vi? sympathetic cooling is also discussed. An example of lg8Hg+ The possibility of making an ultracold positron Ion traps have been used in low energy atomic physics experiments for a period of roughly 30 years.1*2) years, however, the technique of laser cooling and compression has greatly increased the potential use of stored ions in a number of applications. One example is time and frequency standards. With the technique of laser cooling and compression, ion temperatures less than 10 mK, densities a factor of 10 less than the Brillouin limit (defined below), and essentially indefinite confinement times have been obtained. 3,4) Unfortunately, elementary charged particles (electrons, positrons, protons, etc.) can not be directly laser During the past 10
Tracking of signal frequency and/or phase is made much more challenging by the presence of "rapid... more Tracking of signal frequency and/or phase is made much more challenging by the presence of "rapid" frequency or phase changes in a signal-occurring in a time short compared to the amount of frequency shift. In these scenarios, the usual Fourier decomposition does not provide detail sufficient to tell what is going on. Although there are time-frequency tricks one can use (such as the reassigned spectrogram), these do not provide simple answers to the question of what is the phase as a function of time, and they do not track the instantaneous frequency as effectively as is wanted. An interesting solution from the realm of electrical engineering is provided by the phase-locked loop (PLL) detector: a construct that takes the input signal and tries to phase lock an on-board oscillator to it. It turns out that this process is surprisingly effective at tracking instantaneous frequency/phase while discarding noise if an initial estimate of the target signal frequency is known. We present examples of the superior frequency and phase tracking provided by a PLL approach, including the extremely brief chirps produced by electric fish, and the forensic detection of editing cuts in audio samples.
The Journal of the Acoustical Society of America
Intense Positron Beams …, 1988
Radiation pressure from lasers has been used to cool and compress 9Be+ ions stored in a combinati... more Radiation pressure from lasers has been used to cool and compress 9Be+ ions stored in a combination of static electric and magnetic fields (Penning trap) to tem eratures less than 10 mK and densities greater than lo7 cm-q in a magnetic field of 1.4 T. A technique called sympathetic cooling can be used to transfer this cooling and compression to other ion species. ions sympathetically cooled by laser cooled 9Be+ ions is given. source vi? sympathetic cooling is also discussed. A n example of lg8Hg+ The possibility of making an ultracold positron Ion traps have been used in low energy atomic physics experiments for a period of roughly 30 years.1*2) years, however, the technique of laser cooling and compression has greatly increased the potential use of stored ions in a number of applications. One example is time and frequency standards. With the technique of laser cooling and compression, ion temperatures less than 10 mK, densities a factor of 10 less than the Brillouin limit (defined below), and essentially indefinite confinement times have been obtained. 3,4) Unfortunately, elementary charged particles (electrons, positrons, protons, etc.) can not be directly laser During the past 10
... BP Cluggish,a) CF Driscoll, K. Avinash,b) and JA Helffrichc) Department of Physics, 0319, Uni... more ... BP Cluggish,a) CF Driscoll, K. Avinash,b) and JA Helffrichc) Department of Physics, 0319, University of California at San Diego, La Jolla, California 92093 Received 8 November 1996; accepted 27 January 1997 ... n(r,z)dz Q(r). The electrons cool by cyclotron radiation. ...
The beta spectrum of the decay of free molecular tritium has been accurately measured in order to... more The beta spectrum of the decay of free molecular tritium has been accurately measured in order to search for a finite anti nu/sub e/ mass. The betas originating from the decay of free tritium molecules in a differentially pumped source region were momentum analyzed in a toroidal beta spectrometer with 36-eV resolution. The final state effects in molecular tritium are
The beta spectrum of free molecular tritium has been measured in order to search for a finite ele... more The beta spectrum of free molecular tritium has been measured in order to search for a finite electron antineutrino mass. The final-state effects in molecular tritium are accurately known and the data thus yield an essentially model-independent upper limit of 27 eV on the anti ..nu../sub e/ mass at the 95% confidence level. This limit is dominated by the statistics
An experiment to study the beta-decay of tritium using a gaseous source of free (unbound) atomic ... more An experiment to study the beta-decay of tritium using a gaseous source of free (unbound) atomic tritium is currently underway in the Physics Division at Los Alamos. The use of free atomic tritium along with careful design of the measurement scheme should allow a definitive determination for an electron antineutrino mass approx. 10 eV.
The Journal of the Acoustical Society of …, 2012
An apparatus is under construction at Los Alamos to measure the beta spectrum of free tritium ato... more An apparatus is under construction at Los Alamos to measure the beta spectrum of free tritium atoms and molecules. The tritium atoms decay in a gaseous windowless source and are analyzed by a Tret'yakov type toroidal field beta spectrometer. The ultimate sensitivity of the experiment to electron antineutrino mass is expected to be <10 eV.
The primary project goal/objective is to demonstrate the linear motor reciprocating compressor (L... more The primary project goal/objective is to demonstrate the linear motor reciprocating compressor (LMRC) by integrating individually developed technology readiness Level 4 or higher components and to demonstrate that the compressor has improved compression efficiency and a reduced capital and maintenance cost compared to conventional reciprocating compression technology. Another project goal is to meet the flow and pressure requirements in the Multi-Year Research, Development, and Demonstration (MYRDD) Plan tables. The success of these goals will be measured based on the metrics below.
Intense Positron Beams …, 1988
Radiation pressure from lasers has been used to cool and compress 9Be+ ions stored in a combinati... more Radiation pressure from lasers has been used to cool and compress 9Be+ ions stored in a combination of static electric and magnetic fields (Penning trap) to tem eratures less than 10 mK and densities greater than lo7 cm-q in a magnetic field of 1.4 T. A technique called sympathetic cooling can be used to transfer this cooling and compression to other ion species. ions sympathetically cooled by laser cooled 9Be+ ions is given. source vi? sympathetic cooling is also discussed. An example of lg8Hg+ The possibility of making an ultracold positron Ion traps have been used in low energy atomic physics experiments for a period of roughly 30 years.1*2) years, however, the technique of laser cooling and compression has greatly increased the potential use of stored ions in a number of applications. One example is time and frequency standards. With the technique of laser cooling and compression, ion temperatures less than 10 mK, densities a factor of 10 less than the Brillouin limit (defined below), and essentially indefinite confinement times have been obtained. 3,4) Unfortunately, elementary charged particles (electrons, positrons, protons, etc.) can not be directly laser During the past 10
Tracking of signal frequency and/or phase is made much more challenging by the presence of "rapid... more Tracking of signal frequency and/or phase is made much more challenging by the presence of "rapid" frequency or phase changes in a signal-occurring in a time short compared to the amount of frequency shift. In these scenarios, the usual Fourier decomposition does not provide detail sufficient to tell what is going on. Although there are time-frequency tricks one can use (such as the reassigned spectrogram), these do not provide simple answers to the question of what is the phase as a function of time, and they do not track the instantaneous frequency as effectively as is wanted. An interesting solution from the realm of electrical engineering is provided by the phase-locked loop (PLL) detector: a construct that takes the input signal and tries to phase lock an on-board oscillator to it. It turns out that this process is surprisingly effective at tracking instantaneous frequency/phase while discarding noise if an initial estimate of the target signal frequency is known. We present examples of the superior frequency and phase tracking provided by a PLL approach, including the extremely brief chirps produced by electric fish, and the forensic detection of editing cuts in audio samples.
The Journal of the Acoustical Society of America
Intense Positron Beams …, 1988
Radiation pressure from lasers has been used to cool and compress 9Be+ ions stored in a combinati... more Radiation pressure from lasers has been used to cool and compress 9Be+ ions stored in a combination of static electric and magnetic fields (Penning trap) to tem eratures less than 10 mK and densities greater than lo7 cm-q in a magnetic field of 1.4 T. A technique called sympathetic cooling can be used to transfer this cooling and compression to other ion species. ions sympathetically cooled by laser cooled 9Be+ ions is given. source vi? sympathetic cooling is also discussed. A n example of lg8Hg+ The possibility of making an ultracold positron Ion traps have been used in low energy atomic physics experiments for a period of roughly 30 years.1*2) years, however, the technique of laser cooling and compression has greatly increased the potential use of stored ions in a number of applications. One example is time and frequency standards. With the technique of laser cooling and compression, ion temperatures less than 10 mK, densities a factor of 10 less than the Brillouin limit (defined below), and essentially indefinite confinement times have been obtained. 3,4) Unfortunately, elementary charged particles (electrons, positrons, protons, etc.) can not be directly laser During the past 10
... BP Cluggish,a) CF Driscoll, K. Avinash,b) and JA Helffrichc) Department of Physics, 0319, Uni... more ... BP Cluggish,a) CF Driscoll, K. Avinash,b) and JA Helffrichc) Department of Physics, 0319, University of California at San Diego, La Jolla, California 92093 Received 8 November 1996; accepted 27 January 1997 ... n(r,z)dz Q(r). The electrons cool by cyclotron radiation. ...
The beta spectrum of the decay of free molecular tritium has been accurately measured in order to... more The beta spectrum of the decay of free molecular tritium has been accurately measured in order to search for a finite anti nu/sub e/ mass. The betas originating from the decay of free tritium molecules in a differentially pumped source region were momentum analyzed in a toroidal beta spectrometer with 36-eV resolution. The final state effects in molecular tritium are
The beta spectrum of free molecular tritium has been measured in order to search for a finite ele... more The beta spectrum of free molecular tritium has been measured in order to search for a finite electron antineutrino mass. The final-state effects in molecular tritium are accurately known and the data thus yield an essentially model-independent upper limit of 27 eV on the anti ..nu../sub e/ mass at the 95% confidence level. This limit is dominated by the statistics
An experiment to study the beta-decay of tritium using a gaseous source of free (unbound) atomic ... more An experiment to study the beta-decay of tritium using a gaseous source of free (unbound) atomic tritium is currently underway in the Physics Division at Los Alamos. The use of free atomic tritium along with careful design of the measurement scheme should allow a definitive determination for an electron antineutrino mass approx. 10 eV.
The Journal of the Acoustical Society of …, 2012
An apparatus is under construction at Los Alamos to measure the beta spectrum of free tritium ato... more An apparatus is under construction at Los Alamos to measure the beta spectrum of free tritium atoms and molecules. The tritium atoms decay in a gaseous windowless source and are analyzed by a Tret'yakov type toroidal field beta spectrometer. The ultimate sensitivity of the experiment to electron antineutrino mass is expected to be <10 eV.