KATRIN background due to surface radioimpurities

Fränkle, F. M.; Schaller, A.; Blaum, Klaus; Bornschein, L.; Drexlin, G.; Glück, F.; Hannen, V.; Harms, F.; Hinz, D.; Johnston, K.; Karthein, Jonas; Köster, U.; Lokhov, Alexey; Mertens, S.; Müller, F.; Osipowicz, A.; Ranitzsch, P. C.-O.; Thümmler, T.; Trost, N.; Weinheimer, C.; Wolf, J.

doi:10.1016/j.astropartphys.2022.102686

Cited by 11 publications

(15 citation statements)

References 35 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The resulting electrons are accelerated by qUana towards the detector, making them indistinguishable from signal electrons [14,18]. The unstable neutral particles are either 219 Rn and 220 Rn emanated from the getter pumps [19,20] or highly excited atoms sputtered off the inner spectrometer surfaces [21][22][23]. The sputtering mechanisms originate from both α-decays of 210 Po in the structural material and a Penning trap (e), which gives rise to accelerated positive ions from the volume between the two spectrometers [24].…”

Section: Methodsmentioning

confidence: 99%

First direct neutrino-mass measurement with sub-eV sensitivity

Aker¹,

A.²,

Behrens³

et al. 2021

Preprint

Self Cite

View full text Add to dashboard Cite

Section: Methodsmentioning

confidence: 99%

First direct neutrino-mass measurement with sub-eV sensitivity

Aker¹,

A.²,

Behrens³

et al. 2021

Preprint

Self Cite

View full text Add to dashboard Cite

“…Depending on the excitation state of these Rydberg atoms, the ionization electrons will have energies in the meV range. This hypothesis is supported by detailed investigations, including short-term contamination with shorter-lived decay chains from 223 Ra and 228 Th sources [44]. Since the rate of ionization electrons detected depends on the volume imaged by the detector, this background can also be mitigated by the shifted analyzing plane (Sec.…”

Section: Backgroundsmentioning

confidence: 70%

“…As described in Sec. 2.3, our evidence suggests that a significant share of the background electrons in the KATRIN spectrometer originate from highly excited Rydberg atoms, which are ionized by the blackbody radiation emitted from the spectrometer walls at room temperature [44]. These secondary electrons possess very low starting energies [128], but are accelerated by the electric potential gradient of the spectrometer and essentially arrive with the same kinetic energy at the detector as the signal electrons.…”

Section: Active Transverse-energy Filtermentioning

confidence: 76%

KATRIN: Status and Prospects for the Neutrino Mass and Beyond

Aker,

Balzer,

Batzler

et al. 2022

Preprint

Self Cite

View full text Add to dashboard Cite

The Karlsruhe Tritium Neutrino (KATRIN) experiment is designed to measure a high-precision integral spectrum of the endpoint region of T2 β decay, with the primary goal of probing the absolute mass scale of the neutrino. After a first tritium commissioning campaign in 2018, the experiment has been regularly running since 2019, and in its first two measurement campaigns has already achieved a sub-eV sensitivity. After 1000 days of data-taking, KATRIN's design sensitivity is 0.2 eV at the 90 % confidence level. In this white paper we describe the current status of KATRIN; explore prospects for measuring the neutrino mass and other physics observables, including sterile neutrinos and other beyond-Standard-Model hypotheses; and discuss research-anddevelopment projects that may further improve the KATRIN sensitivity.

show abstract

“…The simulation considers the energy spectrum of background electrons which are ionized by black-body radiation at room temperature from hydrogen (36 %) and oxygen atoms (64 %) in highly excited Rydberg states. These Rydberg atoms are sputtered from the spectrometer walls due to α-decays of implanted 210 Pb progenies from the 222 Rn decay chain [5]. The Rydberg atom's energies from [6] are corrected for the surface binding energy and -after ionisation -the electron energy and direction are calculated with the Doppler shift of the Rydberg atoms taken into account.…”

Section: Countsmentioning

confidence: 99%

“…This corresponds to a cyclotron radius at the detector of less than 200 µm 2 . In contrast to the signal electrons, a significant share of the background electrons in the KATRIN spectrometer originate from highly excited, so-called Rydberg atoms, which are ionized by black-body radiation emitted from the spectrometer walls at room temperature [5]. These secondary electrons possess very low starting energies [6], but are accelerated by the electric potential gradient of the spectrometer and arrive at the detector with essentially the same kinetic energy as the signal electrons (which in the central region of the spectrometer also possess energies in the eV range).…”

Section: Introductionmentioning

confidence: 99%

An active transverse energy filter to differentiate low energy particles with large pitch angles in a strong magnetic field

Gauda¹,

Schneidewind²,

Drexlin³

et al. 2022

Preprint

Self Cite

View full text Add to dashboard Cite

We present the idea and proof of principle measurements for an angularselective active filter for charged particles. The motivation for the setup arises from the need to distinguish background electrons from signal electrons in a spectrometer of MAC-E filter type. While a large fraction of the background electrons exhibit predominantly small angles relative to the magnetic guiding field (corresponding to a low amount of kinetic energy in the motion component transverse to the field lines, in the following referred to as transverse energy) and pass the filter mostly unhindered, signal electrons from an isotropically emitting source interact with the active filter and are detected. The concept is demonstrated using a microchannel plate (MCP) as an active filter element. When correctly aligned with the magnetic field, electrons with a small transverse energy pass the channels of the MCP without interaction while electrons with large transverse energies hit the channel walls and trigger an avalanche of secondary electrons that is subsequently detected. Due to several drawbacks of MCPs for an actual transverse energy filter, an alternative detection technique using microstructured Si-PIN diodes is proposed.

show abstract

KATRIN background due to surface radioimpurities

Cited by 11 publications

References 35 publications

First direct neutrino-mass measurement with sub-eV sensitivity

First direct neutrino-mass measurement with sub-eV sensitivity

KATRIN: Status and Prospects for the Neutrino Mass and Beyond

An active transverse energy filter to differentiate low energy particles with large pitch angles in a strong magnetic field

Contact Info

Product

Resources

About