Collective oscillations of a stored deuteron beam close to the quantum limit

We investigated coherent betatron oscillations of a deuteron beam in the storage ring COSY, excited by a detuned radio-frequency Wien filter. These beam oscillations were detected by conventional beam position monitors, read out with lock-in amplifiers. The response of the stored beam to the detuned Wien filter was modelled using the ring lattice and time-dependent 3D field maps of the radio-frequency Wien filter. The influence of uncertain system parameters related to manufacturing tolerances and electronics was investigated using the polynomial chaos expansion. With the currently available apparatus, we show that oscillation amplitudes down to \SI{1}{\micro \meter} can be detected. Future measurements of the electric dipole moment of protons will, however, require control of the relative position of counter-propagating beams in the sub-picometer range. Since the stored beam can be considered as a rarefied gas of uncorrelated particles, we moreover demonstrate that the amplitudes of the zero-point betatron oscillations of individual particles are within a factor of 10 of the Heisenberg uncertainty limit. As a consequence of this, we conclude that quantum mechanics does not preclude the control of the beam centroids to sub-picometer accuracy. The smallest Lorentz force exerted on a single particle that we have been able to determine is \SI{10}{aN}.Comment: 38 pages, 16 figure

Pilot bunch and co-magnetometry of polarized particles stored in a ring

In polarization experiments at storage rings, one of the challenges is to maintain the spin-resonance condition of a radio-frequency spin rotator with the spin-precessions of the orbiting particles. Time-dependent variations of the magnetic fields of ring elements lead to unwanted variations of the spin precession frequency. We report here on a solution to this problem by shielding (or masking) one of the bunches stored in the ring from the high-frequency fields of the spin rotator, so that the masked pilot bunch acts as a co-magnetometer for the other signal bunch, tracking fluctuations in the ring on a time scale of about one second. While the new method was developed primarily for searches of electric dipole moments of charged particles, it may have far-reaching implications for future spin physics facilities, such as the EIC and NICA.Comment: 5 pages, 3 figures + references + supplemental material (6 pages, 2 figures, 6 tables + references

Spin decoherence and off-resonance behavior of radiofrequency-driven spin rotations in storage rings

Radiofrequency-driven resonant spin rotators are routinely used as standard instruments in polarization experiments in particle and nuclear physics. Maintaining the continuous exact parametric spin-resonance condition of the equality of the spin rotator and the spin precession frequency during operation constitutes one of the challenges. We present a detailed analytic description of the impact of detuning the exact spin resonance on the vertical and the in-plane precessing components of the polarization. An important part of the formalism presented here is the consideration of experimentally relevant spin-decoherence effects. We discuss applications of the developed formalism to the interpretation of the experimental data on the novel pilot bunch approach to control the spin-resonance condition during the operation of the radiofrequency-driven Wien filter that is used as a spin rotator in the first direct deuteron electric dipole moment measurement at COSY. We emphasize the potential importance of the hitherto unexplored phase of the envelope of the horizontal polarization as an indicator of the stability of the radiofrequency-driven spin rotations in storage rings. The work presented here serves as a satellite publication to the work published concurrently on the proof of principle experiment about the so-called pilot bunch approach that was developed to provide co-magnetometry for the deuteron electric dipole moment experiment at COSY.Comment: 31 pages, 10 figures, 5 table

First Search for Axionlike Particles in a Storage Ring Using a Polarized Deuteron Beam

Based on the notion that the local dark-matter field of axions or axionlike particles (ALPs) in our Galaxy induces oscillating couplings to the spins of nucleons and nuclei (via the electric dipole moment of the latter and/or the paramagnetic axion-wind effect), we establish the feasibility of a new method to search for ALPs in storage rings. Based on previous work that allows us to maintain the in-plane polarization of a stored deuteron beam for a few hundred seconds, we perform a first proof-of-principle experiment at the Cooler Synchrotron (COSY) to scan momenta near $970  MeV/c$. This entails a scan of the spin-precession frequency. At resonance between the spin-precession frequency of deuterons and the ALP-induced electric dipole moment (EDM) oscillation frequency, there is an accumulation of the polarization component out of the ring plane. Since the axion frequency is unknown, the momentum of the beam and, consequently, the spin-precession frequency are ramped to search for a vertical polarization change that occurs when the resonance is crossed. At COSY, four beam bunches with different polarization directions are used to make sure that no resonance is missed because of the unknown relative phase between the polarization precession and the axion or ALP field. A frequency window of 1.5 kHz width around the spin-precession frequency of 121 kHz is scanned. We describe the experimental procedure and a test of the methodology with the help of a radio-frequency Wien filter located on the COSY ring. No ALP resonance is observed. As a consequence, an upper limit of the oscillating EDM component of the deuteron as well as its axion coupling constants are provided

Culture-level dimensions of social axioms and their correlates across 41 cultures

Leung and colleagues have revealed a five-dimensional structure of social axioms across individuals from five cultural groups. The present research was designed to reveal the culture level factor structure of social axioms and its correlates across 41 nations. An ecological factor analysis on the 60 items of the Social Axioms Survey extracted two factors: Dynamic Externality correlates with value measures tapping collectivism, hierarchy, and conservatism and with national indices indicative of lower social development. Societal Cynicism is less strongly and broadly correlated with previous values measures or other national indices and seems to define a novel cultural syndrome. Its national correlates suggest that it taps the cognitive component of a cultural constellation labeled maleficence, a cultural syndrome associated with a general mistrust of social systems and other people. Discussion focused on the meaning of these national level factors of beliefs and on their relationships with individual level factors of belief derived from the same data set.(undefined

The Target System Development for an Electric Dipole Moment Measurement of Charged Particles at the Cooler Synchrotron COSY

The search for Electric Dipole Moment (EDM) of elementary particles is one of the hottopics in contemporary particle physics. The method to measure charged particle EDMs(proton,deutron) is to observe the time development of a polarized beam in a dedicated storagering (Storage Ring Electric Dipole Moment (srEDM)). This requires a new polarimeterwith a special target system which is under development at Cooler Synchrotron (COSY)-Juelich.The particle detector consists of two layers: a plastic scintillator for ΔE and an inorganicLutetium–yttrium oxyorthosilicate (LYSO) crystal as a calorimeter. Both systems are readoutby multi-pixel silicon photo multiplier (SiPM) arrays. SiPMs operate at significantlylower supply voltages compared to the traditional multi-stage vacuum tubes, simplifying detectorconstruction and operation. The developed calorimeter modules operate at voltagesup to 30 Volt. The fully assembled calorimeter part of the polarimeter has been successfullytested together with its high speed and high-resolution sampling Analog to DigitalConverter (ADC)-based readout. All test have been carried out using solid block target.However, the final polarimeter will include a ballistic target system which will be shootingpoint-like diamond pellet through the beam. Frequency and speed of oscillation must bevariable to achieve desired effective target density. This kind of target will require specialisedmonitoring and control system consisting with several electrical and mechanical parts. Duringthis work, the concept of the pellet target and majority of the electrical and softwareparts has been developed, including precise triggering, object detection, track reconstructionand data synchronization units. Several cameras as well as several image processingalgorithms, different types of sensors and amplifiers have been tested to get the best performance.Fast camera, lasers, photodiodes and Zynq System on Chip (SoC) are used inthe system, Field Programmable Gait Array (FPGA) part is responsible for for fast trigger,Time of Flight (TOF) calculations, image processing and tracking. The ARM CentralProcessing Unit (CPU) is used for communications. Control signals and data are exchangedusing UART interface but in future network interface will be used, which will give us abilityto synchronize data of the target with other systems in detector

A new beam polarimeter at COSY to search for electric dipole moments of charged particles

A calorimetric polarimeter based on inorganic LYSO scintillators is described. It has been designed for use in a storage ring to search for electric dipole moments (EDM) of charged particles such as the proton and deuteron. Its development and first use was on the Cooler Synchrotron (COSY) at the Forschungszentrum Jülich with 0.97 GeV/c polarized deuterons, a particle and energy suitable for an EDM search. The search requires a polarimeter with high efficiency, large analyzing power, and stable operating characteristics. With typical beam momenta of about 1 GeV/c, the scattering of protons or deuterons from a carbon target into forward angles becomes a nearly optimal choice of an analyzing reaction. The polarimeter described here consists of 52 LYSO detector modules, arranged in 4 symmetric blocks (up, down, left, right) for energy determination behind plastic scintillators for particle identification via energy loss. The commissioning results of the current setup demonstrate that the polarimeter is ready to be employed in a first direct measurement for an EDM on the deuteron, which is planned at COSY

Stressors, coping and symptoms of adjustment disorder in the course of the COVID-19 pandemic – study protocol of the European Society for Traumatic Stress Studies (ESTSS) pan-European study

Background: During the current COVID-19 pandemic, the people in Europe are exposed to self-isolation, quarantine, job loss, risk of contracting COVID-19, or grief of loved ones. Such a complex array of stressors may lead to symptoms of adjustment disorder or posttraumatic stress disorder. This research protocol describes a study launched by the European Society of Traumatic Stress Studies (ESTSS) to investigate the impact of the COVID-19 pandemic on symptoms of adjustment disorder across European countries. Objective: The longitudinal online cohort study aims (1) to explore psychosocial reactions to the COVID-19 pandemic across ten European countries; (2) to examine the relationships between risk and resilience factors, stressors and symptoms of adjustment disorder during the pandemic; and (3) to investigate whether these relationships are moderated by coping behaviours. Method: In ten countries (Austria, Croatia, Georgia, Germany, Italy, Lithuania, Netherlands, Poland, Portugal, and Sweden), between 1,000 and 2,000 participants will be recruited, depending on the size of the country. Participants will be assessed at two timepoints with a six-month interval. Following a conceptual framework based on the WHO’s social framework of health, an assessment of risk and resilience factors, COVID-19 related stressors and pandemic-specific coping behaviours will be measured to estimate their contribution to symptoms of adjustment disorder. The Adjustment Disorder New Module 8 (ADNM-8) will be used to assess symptoms of adjustment disorder. As a secondary measure, symptoms of posttraumatic stress disorder will be measure using the Primary Care PTSD Screen for DSM-5 (PC-PTSD-5). Data analysis: The relative contribution of risk factors, resilience factors, and stressors on symptoms of adjustment disorder or symptoms of posttraumatic stress disorder will be estimated using multilevel analysis. To determine the moderating effects of different types of coping behaviours on these relationships, a multilevel mediation analysis will be carried out