ALPS Publications, theses & presentations
Four decades after its prediction, the axion remains the most compelling solution to the Strong-CP problem and a well-motivated dark matter candidate, inspiring a host of elegant and ultrasensitive experiments based on axion-photon mixing. This report reviews the experimental situation on several fronts. We are hopeful, even optimistic, that the next review of the subject will concern the discovery of the axion, its properties, and its exploitation as a probe of early universe cosmology and structure formation.
Ann.Rev.Nucl.Part.Sci. 65, 485-514 (2015)
We present the results of a search for transversely polarised hidden photons (HPs) with ~ 3 eV energies emitted from the Sun. These hypothetical particles, known also as paraphotons or dark sector photons, are theoretically well motivated for example by string theory inspired extensions of the Standard Model.
JCAP 1508 (2015) no.08, 011
Stellar cooling by Weakly Interacting Slim Particles (WISPs), produced in the hot cores and abandoning the star unimpeded, contributing directly to the energy loss. Taken individually, these excesses do not show a strong statistical weight. However, if one mechanism could consistently explain several of them, the hint could be significant. We analyze the hints in terms of neutrino anomalous magnetic moments, minicharged particles, hidden photons and axion-like particles (ALPs). Among them, the ALP represents the best solution. Interestingly, the hinted ALP parameter space is accessible to the next generation proposed ALP searches, such as ALPS II and IAXO.
2015: Quantum Efficiency Characterization and Optimization of a Tungsten Transition-Edge Sensor for ALPS IIThe ALPS II photosensor is a tungsten transition-edge sensor (W-TES) optimized for 1064 nm photons. This TES, operated at 80 mK, has already allowed single infrared photon detections as well as non-dispersive spectroscopy with very low background rates. The demonstrated quantum efficiency for such TES is up to 95% (1064 nm) as has been already demonstrated by the US National Institute of Standards and Technology. A back-to-back measurement of the ALPS TES quantum efficiency using a calibrated charge-coupled device camera has lead to a first estimation of 30%. Improvement methods are discussed.
Journal of Low Temperature Physics (2015)
2015: Characterization, 1064 nm photon signals and background events of a tungsten TES detector for the ALPS experimentThe high efficiency, low-background, and single-photon detection with transition-edge sensors (TES) is making this type of detector attractive in widely different types of application. In this paper, we present first characterizations of a TES to be used in the Any Light Particle Search (ALPS) experiment searching for new fundamental ultra-light particles.
Journal of Modern Optics (2015)
The ALPS II Technical Design Report for the second stage of the “Any Light Particle Search” (ALPS-II) at DESY as submitted to the DESY PRC in August 2012 and reviewed in November 2012. ALPS-II is a “Light Shining through a Wall” experiment which searches for photon oscillations into weakly interacting sub-eV particles. These are often predicted by extensions of the Standard Model and motivated by astrophysical phenomena. Updated in February 2013.
arXiv (1302.5647) and JINST (http://iopscience.iop.org/1748-0221/8/09/T09001/, doi:10.1088/1748-0221/8/09/T09001).
Measurements in the radio regime embrace a number of effective approaches for WISP searches, often covering unique or highly complementary ranges of the parameter space compared to those explored in other research domains. These measurements can be used to search for electromagnetic tracers of the hidden photon and axion oscillations, extending down to ~10^-19 eV the range of the hidden photon mass probed, and closing the last gaps in the strongly favoured 1-5 micro-eV range for axion dark matter. This provides a strong impetus for several new initiatives in the field, including the WISP Dark Matter eXperiment (WISPDMX) and novel conceptual approaches for broad-band WISP searches in the 0.1-1000 micro-eV range.
Standard Model extensions often predict low-mass and very weakly interacting particles, such as the axion. A number of small-scale experiments at the intensity/precision frontier are actively searching for these elusive particles, complementing searches for physics beyond the Standard Model at colliders. Whilst a next generation of experiments will give access to a huge unexplored parameter space, a discovery would have a tremendous impact on our understanding of fundamental physics.
Document developed from a contribution to the Open Symposium of the European Strategy Preparatory Group, 10-12 September 2012, Krakow.
Annalen Phys. 525, A93-A99 (2013)
The ALPS Collaboration started its first “Light Shining through a Wall” experiment to search for photon oscillations into WISPs in 2007. It has been set limits on the existence of Weakly Interacting Sub-eV Particles (WISPs) such as Axion-Like Particles (ALPs), hidden photons and mini-charged particles with a light-shining-through-a-wall setup. These are the most stringent purely laboratory constraints up to date.
Physics Letters B (2010)
Reza Hodajerdi (2015)
Jan Dreyling-Eschweiler (2014)
Jan Eike von Seggern (2014)
Marian Durbeck (September 2015)
Aufbau und Charakterisierung eines 20m Resonators fur ein LSW Experiment
The Ph.D. coffee takes place with ALPS Ph.D. students on different topics to extend knowledge in different areas of physics. Every topic which we present is an interesting and advanced in modern physics.