This research differentiated childhood unpredictability (i.e., perceptions of uncertainty or instability due to turbulent environmental changes) from other related constructs to identify its role in ...adult health. Study 1 (N = 441) showed that, beyond other childhood adversity variables (poverty and adverse childhood experiences or ACEs) and demographic characteristics, perceptions of unpredictability were associated with greater functional disability and worse health-related quality of life (assessed via the CDC’s HRQOL Healthy Days measure and the RAND SF-36). Study 2 (N = 564) replicated those findings in a more racially diverse sample and showed that associations with childhood unpredictability held while also controlling for the Big 5 personality traits. Findings suggest that effects of unpredictability were especially pronounced among Hispanic (in Study 1), and Black/African American and low-income participants (in Study 2). Experiencing childhood environments that are perceived to be uncertain, unstable, or uncontrollable may put children on a path toward poor health outcomes in adulthood. Findings advance theories of child adversity and health and identify childhood unpredictability as a potentially valuable target for intervention.
XENON10 is an experiment designed to directly detect particle dark matter. It is a dual phase (liquid/gas) xenon time-projection chamber with 3D position imaging. Particle interactions generate a ...primary scintillation signal (
S
1
) and ionization signal (
S
2
), which are both functions of the deposited recoil energy and the incident particle type. We present a new precision measurement of the relative scintillation yield
L
eff
and the absolute ionization yield
Q
y
, for nuclear recoils in xenon. A dark matter particle is expected to deposit energy by scattering from a xenon nucleus. Knowledge of
L
eff
is therefore crucial for establishing the energy threshold of the experiment; this in turn determines the sensitivity to particle dark matter. Our
L
eff
measurement is in agreement with recent theoretical predictions above 15
keV nuclear recoil energy, and the energy threshold of the measurement is
∼
4
keV
. A knowledge of the ionization yield
Q
y
is necessary to establish the trigger threshold of the experiment. The ionization yield
Q
y
is measured in two ways, both in agreement with previous measurements and with a factor of 10 lower energy threshold.
Whom do people prefer to have serve as leaders and how does the answer depend on social context? Despite prior research suggesting a preference for dominant leaders during times of war, six ...experiments suggest that people prefer prestige-based leaders (those relying on knowledge and expertise to govern) over dominant leaders (those relying on assertiveness, intimidation, and formal authority as a means of influencing others), even in contexts of intergroup conflict such as war. This preference for prestige-based leaders was explained by perceptions of their trustworthiness, tendency to encourage cooperation, consideration of input from group members, and skillful decision making. However, preference for dominance and prestige did shift in response to social context. Dominant leaders consistently received a boost in support in contexts involving intergroup conflict, whereas prestige-based leaders saw a drop in support. This pattern was specific to intergroup threat and did not generalize to contexts involving a high need for social coordination (e.g., within-group conflict, COVID-19 pandemic). The boost in support for dominant leaders was mediated by perceptions of their ability to enforce collective action (e.g., by punishing free-riders) and to defeat rival groups. The drop in support for prestige-based leaders was mediated by beliefs that their desire for popularity and their strong tendency to prioritize input from group members might undermine their performance and ability to make decisions. These studies provide new insight into why people prefer particular types of leaders, as well as how and why leadership preferences change based on social context. (PsycInfo Database Record (c) 2023 APA, all rights reserved) (Source: journal abstract)
We report on a new measurement of the parity-violating asymmetry in quasielastic electron scattering from the deuteron at backward angles at Q2=0.038 (GeV/c)2. This quantity provides a determination ...of the neutral weak axial vector form factor of the nucleon, which can potentially receive large electroweak corrections. The measured asymmetry A=-3.51+/-0.57 (stat)+/-0.58 (syst) ppm is consistent with theoretical predictions. We also report on updated results of the previous experiment at Q2=0.091 (GeV/c)2, which are also consistent with theoretical predictions.
The violation of mirror symmetry in the weak force provides a powerful tool to study the internal structure of the proton. Experimental results have been obtained that address the role of strange ...quarks in generating nuclear magnetism. The measurement reported here provides an unambiguous constraint on strange quark contributions to the proton's magnetic moment through the electron-proton weak interaction. We also report evidence for the existence of a parity-violating electromagnetic effect known as the anapole moment of the proton. The proton's anapole moment is not yet well understood theoretically, but it could have important implications for precision weak interaction studies in atomic systems such as cesium.
We report a new measurement of the parity-violating asymmetry in elastic electron scattering from the proton at backward scattering angles. This asymmetry is sensitive to the strange magnetic form ...factor of the proton as well as electroweak axial radiative corrections. The new measurement of A = -4.92+/-0.61+/-0.73 ppm provides a significant constraint on these quantities. The implications for the strange magnetic form factor are discussed in the context of theoretical estimates for the axial corrections.
The XENON experiment aims at the direct detection of dark matter in the form of Weakly Interacting Massive Particles (WIMPs) via their elastic scattering off Xe nuclei. A fiducial mass of 1000
kg, ...distributed in 10 independent liquid xenon time projection chambers will be used to probe the lowest interaction cross-section predicted by SUSY models. The TPCs are operated in dual (liquid/gas) phase, to allow a measurement of nuclear recoils down to 16
keV energy, via simultaneous detection of the ionization, through secondary scintillation in the gas, and primary scintillation in the liquid. The distinct ratio of primary to secondary scintillation for nuclear recoils from WIMPs (or neutrons), and for electron recoils from background, is key to the event-by-event discrimination capability of XENON. A dual phase xenon prototype has been realized and is currently being tested, along with other prototypes dedicated to other measurements relevant to the XENON program. As part of the R&D phase, we will realize and move underground a first XENON module (XENON10) with at least 10
kg fiducial mass to measure the background rejection capability and to optimize the conditions for continuous and stable detector operation underground. We present some of the results from the on-going R&D and summarize the expected performance of the 10
kg experiment, from Monte-Carlo simulations. The main design features of the 100
kg detector unit(XENON100), with which we envisage to make up the 1
ton sensitive mass of XENON1T will also be presented.
Constraints on inelastic dark matter from XENON10 Angle, J.; Aprile, E.; Arneodo, F. ...
Physical review. D, Particles, fields, gravitation, and cosmology,
12/2009, Volume:
80, Issue:
11
Journal Article
Open access
It has been suggested that dark matter particles which scatter inelastically from detector target nuclei could explain the apparent incompatibility of the DAMA modulation signal (interpreted as ...evidence for particle dark matter) with the null results from CDMS-II and XENON10. Among the predictions of inelastically interacting dark matter are a suppression of low-energy events, and a population of nuclear recoil events at higher nuclear recoil equivalent energies. This is in stark contrast to the well-known expectation of a falling exponential spectrum for the case of elastic interactions. We present a new analysis of XENON10 dark matter search data extending to E{sub nr} = 75 keV nuclear recoil equivalent energy. Our results exclude a significant region of previously allowed parameter space in the model of inelastically interacting dark matter. In particular, it is found that dark matter particle masses m{sub x} {approx}> 150 GeV are disfavored.
The XENON experiment searches for dark matter particles called WIMPs using liquid xenon (LXe) as the active target. The detector is a 3D position sensitive Time Projection Chamber optimized to ...simultaneously measure the ionization and scintillation produced by a recoil event of energy as low as 16 keV. The distinct ratio of the two signals for nuclear recoils arising from WIMPs and neutrons and for electron recoils from the dominant gamma-ray background determines its event-by-event discrimination. With 1 ton of LXe distributed in ten identical modules, the proposed XENON1T experiment will achieve a sensitivity more than a factor of thousand beyond current limits. A phased program will test a 10 kg detector (XENON10) followed by a 100 kg (XENON100) one as unit module for the XENON1T scale experiment. We review the progress of the XENON R & D phase before presenting the status of XENON10. The experiment will be based at the Gran Sasso Underground Laboratory and is expected to start data taking in early 2006.
In the G0 experiment, performed at Jefferson Lab, the parity-violating elastic scattering of electrons from protons and quasi-elastic scattering from deuterons is measured in order to determine the ...neutral weak currents of the nucleon. Asymmetries as small as 1 part-per-million in the scattering of a polarized electron beam are determined using a dedicated apparatus. It consists of specialized beam monitoring and control systems, a cryogenic hydrogen (or deuterium) target, and a superconducting, toroidal magnetic spectrometer equipped with plastic scintillation and aerogel Cherenkov detectors, as well as fast readout electronics for the measurement of individual events. The overall design and performance of this experimental system is discussed.
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