The field of dark matter detection is a highly visible and highly competitive one. In this paper, we propose recommendations for presenting dark matter direct detection results particularly suited ...for weak-scale dark matter searches, although we believe the spirit of the recommendations can apply more broadly to searches for other dark matter candidates, such as very light dark matter or axions. To translate experimental data into a final published result, direct detection collaborations must make a series of choices in their analysis, ranging from how to model astrophysical parameters to how to make statistical inferences based on observed data. While many collaborations follow a standard set of recommendations in some areas, for example the expected flux of dark matter particles (to a large degree based on a paper from Lewin and Smith in 1995), in other areas, particularly in statistical inference, they have taken different approaches, often from result to result by the same collaboration. We set out a number of recommendations on how to apply the now commonly used Profile Likelihood Ratio method to direct detection data. In addition, updated recommendations for the Standard Halo Model astrophysical parameters and relevant neutrino fluxes are provided. The authors of this note include members of the DAMIC, DarkSide, DARWIN, DEAP, LZ, NEWS-G, PandaX, PICO, SBC, SENSEI, SuperCDMS, and XENON collaborations, and these collaborations provided input to the recommendations laid out here. Wide-spread adoption of these recommendations will make it easier to compare and combine future dark matter results.
The proton light output function in electron-equivalent energy of various scintillators based on linear alkylbenzene (LAB) has been measured in the energy range from 1 MeV to 17.15 MeV for the first ...time. The measurement was performed at the Physikalisch–Technische Bundesanstalt (PTB) using a neutron beam with continuous energy distribution. The proton light output data is extracted from proton recoil spectra originating from neutron–proton scattering in the scintillator. The functional behavior of the proton light output is described successfully by Birks’ law with a Birks constant
kB
between (0.0094±0.0002) cm MeV
−1
and (0.0098±0.0003) cm MeV
−1
for the different LAB solutions. The constant
C
, parameterizing the quadratic term in the generalized Birks law, is consistent with zero for all investigated scintillators with an upper limit (95 % CL) of about 10
−7
cm
2
MeV
−2
. The resulting quenching factors are especially important for future planned supernova neutrino detection based on the elastic scattering of neutrinos on protons. The impact of proton quenching on the supernova event yield from neutrino–proton scattering is discussed.
The use of cryogenic silicon as a detector medium for dark matter searches is gaining popularity. Many of these searches are highly dependent on the value of the photoelectric absorption cross ...section of silicon at low temperatures, particularly near the silicon bandgap energy, where the searches are most sensitive to low mass dark matter candidates. While such cross section data have been lacking from the literature, previous dark matter search experiments have attempted to estimate this parameter by extrapolating it from higher temperature data. However, discrepancies in the high temperature data have led to order-of-magnitude differences in the extrapolations. In this paper, we resolve these discrepancies by using a novel technique to make a direct, low temperature measurement of the photoelectric absorption cross section of silicon at energies near the bandgap (1.2 eV–2.8 eV).
The Formula omitted-particle light response of liquid scintillators based on linear alkylbenzene (LAB) has been measured with three different experimental approaches. In the first approach, Formula ...omitted-particles were produced in the scintillator via Formula omittedC(n, Formula omitted) Formula omittedBe reactions. In the second approach, the scintillator was loaded with 2 % of Formula omittedSm providing an Formula omitted-emitter, Formula omittedSm, as an internal source. In the third approach, a scintillator flask was deployed into the water-filled SNO+ detector and the radioactive contaminants Formula omittedRn, Formula omittedPo and Formula omittedPo provided the Formula omitted-particle signal. The behavior of the observed Formula omitted-particle light outputs are in agreement with each case successfully described by Birks' law. The resulting Birks parameter kB ranges from Formula omitted to Formula omitted cm/MeV. In the first approach, the Formula omitted-particle light response was measured simultaneously with the light response of recoil protons produced via neutron-proton elastic scattering. This enabled a first time a direct comparison of kB describing the proton and the Formula omitted-particle response of LAB based scintillator. The observed kB values describing the two light response functions deviate by more than Formula omitted. The presented results are valuable for all current and future detectors, using LAB based scintillator as target, since they depend on an accurate knowledge of the scintillator response to different particles.
Aligning body, mind and spirit, acquiring emotional intelligence, an unshakable belief in their own intuition and producing outcomes in the context of organisational abilities encompass the ...attributes of leaders that emerged from this holistic exploration of leadership development. Emotionally aware leaders demonstrated their authenticity and cared for peaceful process. In this exploration such leaders started at the bottom within their enterprise working their way up over time. Agreeableness and flexibility were the core competencies they developed amongst others. A complex mix of behaviour, thoughts and emotions were the specific leadership attributes that were found to differ for different organisations. These specific leadership attributes needed to fit with the character and dynamics of the organisation. Since leadership development was found to be a holistic character development over time leadership courses are recommended for all scholars and students, with a strong emphasis on self-development. A grounded theory approach to this holistic exploration of leadership development serves the community well, by promoting the emergence of grounded theories which are free from practical impossibilities.
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