arXiv subjects

Rolf Nahnhauer

Publications and source records attributed to Rolf Nahnhauer.

6 recordsLinked to original sources

arXiv2014

Drilling deep in South Pole Ice

To detect the tiny flux of ultra-high energy neutrinos from active galactic nuclei or from interactions of highest energy cosmic rays with the microwave background photons needs target masses of the order of several hundred cubic kilometers. Clear Antarctic ice has been discussed as a favorable material for hybrid detection of optical, radio and acoustic signals from ultra-high energy neutrino interactions. To apply these technologies at the adequate scale hundreds of holes have to be drilled in the ice down to depths of about 2500 m to deploy the corresponding sensors. To do this on a reasonable time scale is impossible with presently available tools. Remote drilling and deployment schemes have to be developed to make such a detector design reality. After a short discussion of the status of modern hot water drilling we present here a design of an autonomous melting probe, tested 50 years ago to reach a depth of about 1000 m in Greenland ice. A scenario how to build such a probe today with modern technologies is sketched. A first application of such probes could be the deployment of calibration equipment at any required position in the ice, to study its optical, radio and acoustic transmission properties.

physics.ins-det↗

arXiv2012

The next-generation liquid-scintillator neutrino observatory LENA

We propose the liquid-scintillator detector LENA (Low Energy Neutrino Astronomy) as a next-generation neutrino observatory on the scale of 50 kt. The outstanding successes of the Borexino and KamLAND experiments demonstrate the large potential of liquid-scintillator detectors in low-energy neutrino physics. LENA's physics objectives comprise the observation of astrophysical and terrestrial neutrino sources as well as the investigation of neutrino oscillations. In the GeV energy range, the search for proton decay and long-baseline neutrino oscillation experiments complement the low-energy program. Based on the considerable expertise present in European and international research groups, the technical design is sufficiently mature to allow for an early start of detector realization.

astro-ph.IM↗

arXiv2012

Acoustic detection of ultra-high energetic neutrinos - a snap shot

Already more than 30 years ago the acoustic particle detection method has been considered to be one possibility to measure signals from ultra-high energetic neutrinos. The present status and problems of corresponding model predictions are discussed in comparison with existing experimental measurements. Available acoustic sensors and transmitters are described and new ideas for corresponding applications are mentioned. Different methods for in-situ calibrations are discussed. Results of measurements of acoustic test arrays at different sites are presented in some detail. Future activities for applications of the technology in large size detectors are evaluated.

astro-ph.IM↗

arXiv2011

Design and performance of the South Pole Acoustic Test Setup

The South Pole Acoustic Test Setup (SPATS) was built to evaluate the acoustic characteristics of the South Pole ice in the 10 kHz to 100 kHz frequency range, for the purpose of assessing the feasibility of an acoustic neutrino detection array at the South Pole. The SPATS hardware consists of four vertical strings deployed in the upper 500 m of the South Pole ice cap. The strings form a trapezoidal array with a maximum baseline of 543 m. Each string has 7 stages equipped with one transmitter and one sensor module. Sound is detected or generated by piezoelectric ceramic elements inside the modules. Analogue signals are sent to the surface on electric cables where they are digitized by a PC-based data acquisition system. The data from all strings are collected on a central computer in the IceCube Laboratory from where they are send to a central data storage facility via a satellite link or stored locally on tape. A technical overview of SPATS and its performance is presented.

astro-ph.IM↗

arXiv2011

Acoustic particle detection - from early ideas to future benefits

The history of acoustic neutrino detection technology is shortly reviewed from first ideas 50 years ago to the detailed R&D programs of the last decade. The physics potential of ultra-high energy neutrino interaction studies is discussed for some examples. Ideas about the necessary detector size and suitable design are presented.

astro-ph.IM↗

arXiv2004

Alternative Detection Methods for Highest Energy Neutrinos

Several experimental techniques are currently under development, to measure the expected tiny fluxes of highest energy neutrinos above 10**18 eV. Projects in different stages of realisation are discussed here, which are based on optical and radio as well as acoustic detectors. For the detection of neutrino events in this energy range a combination of different detector concepts in one experiment seems to be most promising.

astro-ph↗