5 research outputs found
Time-Focusing Time-of-Flight, a new method to turn a MAC-E-filter into a quasi-differential spectrometer
Spectrometers based on the magnetic adiabatic collimation followed by an
electrostatic filter (MAC-E-filter) principle combine high angular acceptance
with an excellent energy resolution. These features make MAC-E-filters very
valuable for experiments where the kinetic energy of ions or electrons from
rare processes has to be measured with utmost sensitivity and precision.
Examples are direct neutrino mass experiments like KATRIN which investigate the
energy of electrons in the endpoint region of the tritium -spectrum.
However, the MAC-E-filter is a very sharp energy high-pass filter but not a
differential spectrometer. To determine a spectral shape of a charged particle
source, different electric retarding potentials have to be used sequentially,
reducing the statistics.
In a previous work we have shown that the advantages of the standard
MAC-E-filter can be combined with a measurement of the time-of-flight (TOF),
allowing to determine spectral information over a certain energy range with one
retarding potential only, with the corresponding gain in statistics. This TOF
method requires to know the start time of the charged particles, which is not
always possible. Therefore, we propose a new method which does not require the
determination of the start time and which we call "time-focusing
Time-of-Flight" (tfTOF): By applying a time dependent acceleration and
deceleration potential at a subsequent MAC-E-filter, an energy dependent
post-bunching of the charged particles is achieved.Comment: 10 pages, 9 figures, submitted to Eur. Phys. J.
First operation of the KATRIN experiment with tritium
The determination of the neutrino mass is one of the major challenges in astroparticle physics today. Direct neutrino mass experiments, based solely on the kinematics of β
β
-decay, provide a largely model-independent probe to the neutrino mass scale. The Karlsruhe Tritium Neutrino (KATRIN) experiment is designed to directly measure the effective electron antineutrino mass with a sensitivity of 0.2 eV
0.2 eV
(90%
90%
CL). In this work we report on the first operation of KATRIN with tritium which took place in 2018. During this commissioning phase of the tritium circulation system, excellent agreement of the theoretical prediction with the recorded spectra was found and stable conditions over a time period of 13 days could be established. These results are an essential prerequisite for the subsequent neutrino mass measurements with KATRIN in 2019
Recommended from our members
Quantitative Long-Term Monitoring of the Circulating Gases in the KATRIN Experiment Using Raman Spectroscopy.
The Karlsruhe Tritium Neutrino (KATRIN) experiment aims at measuring the effective electron neutrino mass with a sensitivity of 0.2 eV/c2, i.e., improving on previous measurements by an order of magnitude. Neutrino mass data taking with KATRIN commenced in early 2019, and after only a few weeks of data recording, analysis of these data showed the success of KATRIN, improving on the known neutrino mass limit by a factor of about two. This success very much could be ascribed to the fact that most of the system components met, or even surpassed, the required specifications during long-term operation. Here, we report on the performance of the laser Raman (LARA) monitoring system which provides continuous high-precision information on the gas composition injected into the experiment's windowless gaseous tritium source (WGTS), specifically on its isotopic purity of tritium-one of the key parameters required in the derivation of the electron neutrino mass. The concentrations cx for all six hydrogen isotopologues were monitored simultaneously, with a measurement precision for individual components of the order 10-3 or better throughout the complete KATRIN data taking campaigns to date. From these, the tritium purity, εT, is derived with precision of <10-3 and trueness of <3 × 10-3, being within and surpassing the actual requirements for KATRIN, respectively
Quantitative Long-Term Monitoring of the Circulating Gases in the KATRIN Experiment Using Raman Spectroscopy.
The Karlsruhe Tritium Neutrino (KATRIN) experiment aims at measuring the effective electron neutrino mass with a sensitivity of 0.2 eV/c2, i.e., improving on previous measurements by an order of magnitude. Neutrino mass data taking with KATRIN commenced in early 2019, and after only a few weeks of data recording, analysis of these data showed the success of KATRIN, improving on the known neutrino mass limit by a factor of about two. This success very much could be ascribed to the fact that most of the system components met, or even surpassed, the required specifications during long-term operation. Here, we report on the performance of the laser Raman (LARA) monitoring system which provides continuous high-precision information on the gas composition injected into the experiment's windowless gaseous tritium source (WGTS), specifically on its isotopic purity of tritium-one of the key parameters required in the derivation of the electron neutrino mass. The concentrations cx for all six hydrogen isotopologues were monitored simultaneously, with a measurement precision for individual components of the order 10-3 or better throughout the complete KATRIN data taking campaigns to date. From these, the tritium purity, εT, is derived with precision of <10-3 and trueness of <3 × 10-3, being within and surpassing the actual requirements for KATRIN, respectively