HighRR Workshop: Vistas on Detector Physics

30 Sept 2019, 09:00 → 1 Oct 2019, 18:00 Europe/Zurich

00.101-00.103 (Goldbox) (Physikalisches Institut)

Loredana Gastaldo (Heidelberg University), Hannah Klingenmeyer (Kirchhoff Institute for Physics, Heidelberg University), Andre Schoening (Ruprecht Karls Universitaet Heidelberg (DE)), Hans-Christian Schultz-Coulon (Ruprecht Karls Universitaet Heidelberg (DE)), Johanna Stachel (Ruprecht Karls Universitaet Heidelberg (DE))

The workshop “Vistas on Detector Physics” aims to open a window on recent detector development in fields as high energy physics, neutrino physics, dark matter searches and in experiments to better understand our Universe. This workshop is mainly addressed to undergraduate and PhD students.

The wide spectrum of detector technologies presented during the different sessions will give the opportunity to the participants to deepen the knowledge on new devices. The informal style of this workshop will foster lively discussion with experts in detector development.

The workshop “Vistas on Detector Physics” is supported by the “High Resolution and High Rate Detectors in Nuclear and Particle Physics” (HighRR) Research Training Group. HighRR is dedicated to research and education in pure detector science. It particularly focuses on the instrumentation of novel experiments in nuclear, particle and high energy physics.

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Monday, 30 September

09:00 → 09:30 Registration and Coffee

09:30 → 09:45 Day 1: Welcome

09:30 Welcome

09:45 → 10:30 Day 1: High resolution and high rate detectors

09:45 Detector Developments for Photon Science at DESY

Over the past decade or so, DESY's Photon Science Detector group has spearheaded a number of developments - motivated by the dire need for faster large-area imagers with high dynamic range that is a direct consequence of the advances in synchrotron light sources and free electron lasers.
In particular, the Adaptive Gain Integrating Pixel Detector (AGIPD) provides a Megapixel array running at up to 6 MHz frame rates during Eu.XFEL's bunch trains, it was used to take first-light images at the European XFEL. Today, variants utilizing high-Z material and a yet-larger 4-Megapixel-Array with more compact electronics are under development.
For soft X-ray applications, the Pixelated Energy Resolving CMOS Imager, Versatile And Large (PERCIVAL) was conceived and is today being brought to operation by an international collaboration of light sources. It provides 2 Megapixels in a single 4.5x5cm2 CMOS imager with 27x27um2 pixels and spans single photon discrimination to over 10^4 photons/pixel/frame; its primary foreseen operating range is 250eV-1keV. For soft X-ray imagers, as well as for e.g. UV detection, backside-illuminated sensors with ultrathin entrance windows are required and pose their own challenges.
Experiments at future light sources - both FELs and diffraction-limited synchrotrons - will require detectors that can acquire full multi megapixel images continuously at frame rates of 100kHz and more. This requires new system architectures, from readout ASIC through the front end to DAQ backend.

Speaker: C. Wunderer

10:30 → 11:00 Coffee Break

11:00 → 12:30 Day 1: Axions and axion-like particles

11:00 The ALPS II Experiment and its TES Detector

The Any Light Particle Search II (ALPS II) experiment at DESY will look for axion-like particles (ALPs) with low masses ($m<10^{-4}$ eV). ALPS II is a purely laboratory-based experiment, where ALPs could be produced and detected employing the light-shining-through-wall (LSW) technique using infrared photons with a wavelength of 1064 nm. ALPS II utilizes the concept of resonant enhancement on the production and regeneration side to improve the sensitivity of traditional LSW-experiments. The experiment requires a detection system capable of observing infrared photons at extremely small rates of the order of $10^{-5}s^{-1}$. For this purpose a system based on a transition edge sensor (TES), i.e. a cryogenic calorimeter, which exploits the drastic dependence of a material’s electrical resistance on the temperature in its transition region, is being developed. The talk will present the current status of ALPS II with special focus on the TES detection system.

Speaker: F. Januschek

11:45 Probing the axion-electron coupling in cm-scale atomic targets

In well-motivated extensions of the Standard Model to solve the strong CP problem of quantum chromodynamics, axions emerge as leading candidates of non-WIMP dark matter. In this seminar, we discuss tabletop-scale experiments in axion detection, particularly focusing on new observables for direct detection of axion dark matter. For instance, axion interactions with electrons in condensed matter would produce spin flips in a ferrimagnetic sample (QUAX), or excite the upper Zeeman level of rare earth atoms in suitable rare-earth doped crystalline matrices (AXIOMA). The experimental parameters required to achieve cosmologically relevant sensitivity in both approaches will be briefly discussed.

Speaker: C. Braggio

12:30 → 14:00 Lunch Break

14:30 → 16:00 Day 1: High Energy Physics detectors

14:30 Monolithic silicon pixel detectors in HEP

Speaker: P. Riedler

15:15 The World’s Fastest Time Projection Chamber

Speaker: Y. Pachmayer

16:00 → 16:30 Coffee Break

16:30 → 18:00 Day 1: Astronomy and Astrophysics

16:30 Gamma-ray and Neutron Spectrometers for Planetary Science Missions

Gamma ray and/or neutron spectrometers have been flown on planetary spaceflight missions since the USSR’s Luna-10 mission first used a gamma ray spectrometer to study the composition of the Moon from lunar orbit. Due to nuclear interactions with galactic cosmic rays (or a separate source of high energy neutrons), planetary materials emit gamma rays and neutrons that can be measured to determine the elemental composition of the planet down to ~ 1 meter below the surface. This subsurface composition information is critical to a better understanding of the planet’s formation and evolution. This talk will be focused on the challenges surrounding the development of such gamma ray and neutron detectors for planetary science space missions. The physical processes that produce the planetary gamma rays and neutrons will be described along with the requirements for their detection. Detector design and development challenges will be discussed and examples of past and future missions will be presented to illustrate how these detectors must be tailored to specific mission architectures and planetary compositions.

Speaker: A. Parsons

17:15 LISA: Gravitational wave observation from space

Gravitational waves are a hot topic, after their first detection by the LIGO observatories in 2015 and the nobel prize award in 2017.
While the success story of the ground based detectors continues, the scientific community is busy preparing the next steps in gravitational wave observation. One of these next steps is launching a space based gravitational wave observatory: LISA, the “Laser Interferometer Space Antenna”, which is currently planned to launch in 2034. In this talk, I will give an introduction to LISA as well as to gravitational waves, their observation from ground and space, and what we gain by doing both.

Speaker: G. Wanner

19:00 → 21:00 Welcome Party

Tuesday, 1 October

09:00 → 10:30 Day 2: Dark Matter I

09:00 CRESST-III: Low temperature detectors for low-mass dark matter searches

The CRESST-III experiment searches for direct interactions of dark matter with ordinary matter at the Laboratori Nazionali del Gran Sasso (LNGS) in Italy. The main event signature would be a nuclear recoil in the scintillating target crystals.
Operating the crystals as cryogenic calorimeters at O (10 mK), CRESST-III can simultaneously measure the phonon signal from CaWO4 and the emitted scintillation light in a separate cryogenic light detector. This provides particle discrimination on an event-by-event basis allowing for and active discrimination of backgrounds.
CRESST-III focuses on the sub-GeV/c mass region where the sensitivity is driven by the threshold. With a CaWO4 crystal of 24 g as target an unprecedented low threshold of 30 eV for nuclear recoils was obtained in the first data taking campaign of CRESST-III from 2016-2018.
In this contribution, the status of the experiment will be reported, together with the latest results both on spin-dependent and spin-independent searches.

Speaker: L. Canonica

09:45 DARWIN: the next-generation of xenon time projection chambers

Most promising detectors to search for particle dark matter are the xenon dual-phase time projection chambers (TPCs). This technology is by now well-established and can be scaled up to ton-scale. In this context, the XENON1T experiment currently holds the world-leading limit for direction detection of Weakly Interacting Massive Particles (WIMPs). Their next stage, XENONnT, will get a better sensitivity due to a much-increased exposure and a better self-shielding. And finally, DARWIN, a proposed next-generation TPC, with 50 tonnes of natural xenon, will be able to explore the entire experimentally accessible parameter space for WIMPs. Besides this unprecedented sensitivity to WIMPS, a large detector like DARWIN, with its low-energy threshold and ultra low background level, will be sensitive to other rare interactions as well.

Speaker: P. Sanchez Lucas

10:30 → 11:00 Coffee Break

11:00 → 12:30 Day 2: Dark Matter II

11:00 The DARKSIDE experiment

Speaker: G. Fiorillo

11:45 Dark matter search with DEAP-3600

The DEAP-3600 experiment is searching for WIMP dark matter with a 3.3 tonne single-phase liquid argon (LAr) target. Detector construction was completed at SNOLAB in 2016, and the experiment is currently taking physics data. Results from 1 year of open data (758 tonne-day exposure) were recently published, demonstrating stable detector operation and the power of pulse shape discrimination to reject electron-recoil backgrounds in LAr. This background-free search currently provides the most sensitive WIMP-nucleon scattering cross section limit on a LAr target for WIMP masses above 30 GeV.
This talk will focus on the design, construction, and calibration of the DEAP-3600 detector.

Speaker: T. Pollmann

12:30 → 14:00 Lunch Break

14:30 → 16:00 Day 2: Neutrinos

14:30 Precision High Voltage and Energy Loss Analysis at the KATRIN Experiment

The Karlsruhe Tritium Neutrino experiment (KATRIN) aims to determine the neutrino mass by measuring the tritium beta decay spectrum with a sensitivity of 0.2 eV (90 % C.L.). To reach this goal the spectrometer’s energy scale needs to be stable on the 60 meV level. This translates to a 3 ppm stability requirement for the high voltage creating the retarding potential (18.6 kV). The high voltage system outperforms this requirement with a stability of 2 ppm and is therefore a negligible systematic for the neutrino mass analysis.
Another important systematic are energy losses of beta decay electrons inside the windowless gaseous tritium source (WGTS) of KATRIN. Using mono-energetic electrons from a photo-electron source and applying a time-of-flight analysis we performed measurements of energy losses inside the WGTS. These in-situ measurements provide an energy loss shape with unprecedented precision.
The talk will give an overview of both topics with regard to the results from KATRIN’s most recent science run in spring 2019. This project is supported by BMBF under contract number 05A17PM3.

Speaker: C. Rodenbeck

15:00 Tritium spectroscopy and event detection in Project 8

Speaker: C. Claessens

15:30 The ECHo experiment

The goal of the Electron Capture in Holmium-163 (ECHo) experiment is the determination of the electron neutrino mass by the analysis of the electron capture spectrum of Holmium-163. The detector technology is based on metallic magnetic calorimeters operated at low temperature in a reduced background environment. During the first phase of the experiment, ECHo-1k, the detector production has been optimised and the implantation process of high purity 163Ho source in large detector arrays has been developed. The implanted detectors have been successfully operated and characterised at low temperatures, reaching energy resolution below 5 eV. High statistics and high resolution Holmium-163 spectra have been acquired and analysed at the light of the new developed theoretical description of the spectral shape, considering the independently determined value of the energy available to the EC process and a dedicated background model. In this contribution, we present preliminary results obtained in the first phase of ECHo. At the same time we discuss the necessary upgrades towards the second phase of the experiment, ECHo-100k. In particular, we focus on the production of large arrays with Holmium-163 embedded in the absorbers and on the multiplexed readout.

Speaker: F. Mantegazzini

16:00 → 16:30 Coffee Break

16:30 → 18:00 Day 2: BSM/ Neutrino physics

16:30 Looking for coherent elastic neutrino nucleus scattering with Ge detectors

When neutrinos interact via coherent elastic scattering with a nucleus, a tiny recoil is created. To be able to detect this recoil, special requirements have to be met. Detectors with a low enough noise threshold are needed and only recent developments make it possible to access the energy range where a detection is possible. Moreover, a large neutrino flux at energies within the regime of the coherent interaction is demanded with the prime candidates being neutrinos from nuclear power plants or pion decay at rest sources. As these sources are located at shallow depth, special attention has to be paid at the suppression of cosmogenic induced backgrounds.
The talk will focus on the high-purity point contact Germanium detectors employed by the CONUS experiment located at the nuclear power plant of Brokdorf, Germany, at 17m distance from the reactor core. The special circumstances at the nuclear power plant deviate far from laboratory conditions which leads to particular demands at the detector technology. Moreover, especially reactor correlated backgrounds have to be carefully characterized and an elaborated shield is needed to suppress them. In the talk it will be presented how these challenges are met for the CONUS experiment.

Speaker: J. Hakenmüller

talk_vistas_jhakenmueller.pdf

17:00 Understanding signal shapes from germanium detectors

The GERDA and MAJORANA experiments are searching for neutrinoless double-beta decay with germanium detectors enriched in the double-beta decaying isotope Ge-76. Building on their success in reaching background-free conditions and excellent energy resolution, the LEGEND experiment is planned to continue this search in a staged approach. One of the most efficient offline background reduction techniques in these searches is pulse shape discrimination using the signal shape coming from the Ge detectors. In order to understand and distinguish the signal shape from different background sources, simulations and test measurements are performed. I will introduce the concepts of signal generation in germanium detectors by presenting a new open source pulse shape simulation software developed at the MPI for Physics. Also I will discuss some of our test stand measurements studying surface effects and temperature dependence.

Speaker: A. Zsigmond

17:30 The SHiP Liquid Scintillator Surrounding Background Tagger

The SHiP experiment has been proposed as a general-purpose fixed-target facility at the CERN SPS North Area, with the start of data taking scheduled for 2026. Consisting of a two-fold detector, it combines the Search for Hidden Particles (SHiP) - such as Heavy Neutral Leptons (HNL) and light dark matter - with studies of tau neutrino physics.
The impact of the high-intensity 400 GeV/c proton beam on the hybrid target may create HNL via the decay of heavy mesons and other weakly interacting particles of masses m <= 10 GeV/c^2. After a hadron absorber and an active muon shield, these particles are expected to decay inside a large vacuum vessel which is followed by a magnetic spectrometer and a calorimeter. To discriminate against external particle interactions, the decay vessel will be covered by the Surrounding Background Tagger (SBT).
This talk will give a general overview of the SHiP experiment, then focus on the current design of and ongoing R&D on the segmented liquid scintillator option for the SBT detector.

Speaker: A. Hollnagel