1,282 research outputs found
DAMA annual modulation effect and asymmetric mirror matter
The long-standing model-independent annual modulation effect measured by DAMA
Collaboration is examined in the context of asymmetric mirror dark matter,
assuming that dark atoms interact with target nuclei in the detector via
kinetic mixing between mirror and ordinary photons, both being massless. The
relevant ranges for the kinetic mixing parameter are obtained taking into
account various existing uncertainties in nuclear and particle physics
quantities as well as characteristic density and velocity distributions of dark
matter in different halo models.Comment: 27 pages, 5 figures, 2 tables; version in publication on Eur. Phys.
J.
Narrative Health Communication and Behavior Change: The Influence of Exemplars in the News on Intention to Quit Smoking.
This study investigated psychological mechanisms underlying the effect of narrative health communication on behavioral intention. Specifically, the study examined how exemplification in news about successful smoking cessation affects recipients\u27 narrative engagement, thereby changing their intention to quit smoking. Nationally representative samples of U.S. adult smokers participated in 2 experiments. The results from the 2 experiments consistently showed that smokers reading a news article with an exemplar experienced greater narrative engagement compared to those reading an article without an exemplar. Those who reported more engagement were in turn more likely to report greater smoking cessation intentions
Observations of annual modulation in direct detection of relic particles and light neutralinos
The long-standing model-independent annual modulation effect measured by the
DAMA Collaboration, which fulfills all the requirements of a dark matter annual
modulation signature, and the new result by the CoGeNT experiment that shows a
similar behavior are comparatively examined under the hypothesis of a dark
matter candidate particle interacting with the detectors' nuclei by a coherent
elastic process. The ensuing physical regions in the plane of the dark
matter-particle mass versus the dark matter-particle nucleon cross-section are
derived for various galactic halo models and by taking into account the impact
of various experimental uncertainties. It is shown that the DAMA and the CoGeNT
regions agree well between each other and are well fitted by a supersymmetric
model with light neutralinos which satisfies all available experimental
constraints, including the most recent results from CMS and ATLAS at the CERN
Large Hadron Collider.Comment: 13 pages, 7 figure
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Lost Voices of Hagia Sophia: Medieval Byzantine Chant Sung in the Virtual Acoustics of Hagia Sophia. The Feast of the Exaltation of the Holy Cross in Constantinople
3D surface acquisition systems and their applications to facial anatomy : let’s make a point
In the last decades 3D optical devices have gained a primary role in facial anthropometry, where they find several applications from the anatomical research to clinics and surgery. With time the number of articles focusing on 3D surface analysis has raised, as well as validation studies which aim at verifying the reliability of different devices and methods of acquisition in comparison with other methods or direct anthropometry. This review aims at making a point in the field of 3D surface acquisition systems, describing the most used types of available devices and comparing the relevant outcomes in acquiring 3D facial models. Results show that currently stereophotogrammetric devices represent the gold standard, further improved by the diffusion of portable models. Caution should be given to the use of low-cost devices, more and more frequently described by literature, as often they do not meet the basic criteria for being applied to the anatomical study of face
Lower Nicotine Cigarettes may not Lower Harm
In 2005, nearly 21% of American adults smoked cigarettes, and 81% of them smoked every day. For smokers unable or unwilling to quit, tobacco products that reduce the adverse health effects of smoking may be an attractive option. Potentially reduced exposure products (PREPs) were developed by the tobacco industry in response to smokers’ health concerns. PREPs purportedly lower the tar and/or nicotine levels of cigarettes, although the actual harm reduced remains questionable. One of the most recent additions to this product class are cigarettes that use genetically modified tobacco to reduce nicotine levels. This Issue Brief summarizes studies that investigate [1] how this product is used and [2] the messages smokers take away from product marketing. These complementary studies send a cautionary signal about the ability of these new cigarettes to reduce the harmful effects of smoking
Final results of an experiment to search for 2beta processes in zinc and tungsten with the help of radiopure ZnWO4 crystal scintillators
A search for the double beta decay of zinc and tungsten isotopes has been
performed with the help of radiopure ZnWO4 crystal scintillators (0.1-0.7 kg)
at the Gran Sasso National Laboratories of the INFN. The total exposure of the
low background measurements is 0.529 kg yr. New improved half-life limits on
the double beta decay modes of 64Zn, 70Zn, 180W, and 186W have been established
at the level of 10^{18}-10^{21} yr. In particular, limits on double electron
capture and electron capture with positron emission in 64Zn have been set:
T_{1/2}(2\nu 2K) > 1.1 10^{19} yr, T_{1/2} (0\nu 2\epsilon) > 3.2 10^{20} yr,
T_{1/2} (2\nu \epsilon \beta^+) > 9.4 10^{20} yr, and T_{1/2} (0\nu \epsilon
\beta^+) > 8.5 10^{20} yr, all at 90% C.L. Resonant neutrinoless double
electron capture in 180W has been restricted on the level of T_{1/2} (0\nu
2\epsilon) > 1.3 10^{18} yr. A new half-life limit on alpha transition of 183W
to the metastable excited level 1/2^- 375 keV of 179Hf has been established:
T_{1/2} > 6.7 10^{20} yr.Comment: This is an author-created, un-copyedited version of an article
published in J. Phys. G: Nucl. Part. Phys. IOP Publishing Ltd is not
responsible for any errors or omissions in this version of the manuscript or
any version derived from it. The definitive publisher authenticated version
is available online at doi: 10.1088/0954-3899/38/11/11510
Investigation of rare nuclear decays with BaF crystal scintillator contaminated by radium
The radioactive contamination of a BaF scintillation crystal with mass of
1.714 kg was measured over 101 hours in the low-background DAMA/R&D set-up deep
underground (3600 m w.e.) at the Gran Sasso National Laboratories of INFN
(LNGS, Italy). The half-life of Po (present in the crystal scintillator
due to contamination by radium) was measured as Po) =
298.80.8(stat.)1.4(syst.) ns by analysis of the events' pulse
profiles. The Rn nuclide is known as 100% decaying via emission of
particle with = 3.82 d; however, its decay is also
energetically allowed with keV. Search for decay chains of
events with specific pulse shapes characteristic for or for
signals and with known energies and time differences allowed us
to set, for the first time, the limit on the branching ratio of Rn
relatively to decay as % at 90% C.L. (equivalent to
limit on partial half-life y). Half-life limits of
Pb, Rn and Ra relatively to decays are also
improved in comparison with the earlier results.Comment: 10 pages, 9 figures, 2 table
Search for long-lived superheavy eka-tungsten with radiopure ZnWO crystal scintillator
The data collected with a radioactively pure ZnWO crystal scintillator
(699 g) in low background measurements during 2130 h at the underground (3600 m
w.e.) Laboratori Nazionali del Gran Sasso (INFN, Italy) were used to set a
limit on possible concentration of superheavy eka-W (seaborgium Sg, Z = 106) in
the crystal. Assuming that one of the daughters in a chain of decays of the
initial Sg nucleus decays with emission of high energy particle
( MeV) and analyzing the high energy part of the measured
spectrum, the limit N(Sg)/N(W) < 5.5 10 atoms/atom at
90% C.L. was obtained (for Sg half-life of 10 yr). In addition, a limit on
the concentration of eka-Bi was set by analysing the data collected with a
large BGO scintillation bolometer in an experiment performed by another group
[L. Cardani et al., JINST 7 (2012) P10022]: N(eka-Bi)/N(Bi) < 1.1
10 atoms/atom with 90% C.L. Both the limits are comparable with those
obtained in recent experiments which instead look for spontaneous fission of
superheavy elements or use the accelerator mass spectrometry.Comment: 9 pages, 2 figures; in press on Physica Script
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