اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدDesign Overview of the DM Radio Pathfinder Experiment
89
0
0.0
(
0
)
اسأل ChatGPT حول البحث
ﻻ يوجد ملخص باللغة العربية
We introduce the DM Radio, a dual search for axion and hidden photon dark matter using a tunable superconducting lumped-element resonator. We discuss the prototype DM Radio Pathfinder experiment, which will probe hidden photons in the 500 peV (100 kHz)-50 neV (10 MHz) mass range. We detail the design of the various components: the LC resonant detector, the resonant frequency tuning procedure, the differential SQUID readout circuit, the shielding, and the cryogenic mounting structure. We present the current status of the pathfinder experiment and illustrate its potential science reach in the context of the larger experimental program.
قيم البحث
اقرأ أيضاً
We designed, fabricated, and characterized four arrays of horn--coupled, lumped element kinetic inductance detectors (LEKIDs), optimized to work in the spectral bands of the balloon-borne OLIMPO experiment. OLIMPO is a 2.6 m aperture telescope, aimed
at spectroscopic measurements of the Sunyaev-Zeldovich (SZ) effect. OLIMPO will also validate the LEKID technology in a representative space environment. The corrected focal plane is filled with diffraction limited horn-coupled KID arrays, with 19, 37, 23, 41 active pixels respectively at 150, 250, 350, and 460$:$GHz. Here we report on the full electrical and optical characterization performed on these detector arrays before the flight. In a dark laboratory cryostat, we measured the resonator electrical parameters, such as the quality factors and the electrical responsivities, at a base temperature of 300$:$mK. The measured average resonator $Q$s are 1.7$times{10^4}$, 7.0$times{10^4}$, 1.0$times{10^4}$, and 1.0$times{10^4}$ for the 150, 250, 350, and 460$:$GHz arrays, respectively. The average electrical phase responsivities on resonance are 1.4$:$rad/pW, 1.5$:$rad/pW, 2.1$:$rad/pW, and 2.1$:$rad/pW; the electrical noise equivalent powers are 45$:rm{aW/sqrt{Hz}}$, 160$:rm{aW/sqrt{Hz}}$, 80$:rm{aW/sqrt{Hz}}$, and 140$:rm{aW/sqrt{Hz}}$, at 12 Hz. In the OLIMPO cryostat, we measured the optical properties, such as the noise equivalent temperatures (NET) and the spectral responses. The measured NET$_{rm RJ}$s are $200:murm{Ksqrt{s}}$, $240:murm{Ksqrt{s}}$, $240:murm{Ksqrt{s}}$, and $:340murm{Ksqrt{s}}$, at 12 Hz; under 78, 88, 92, and 90 mK Rayleigh-Jeans blackbody load changes respectively for the 150, 250, 350, and 460 GHz arrays. The spectral responses were characterized with the OLIMPO differential Fourier transform spectrometer (DFTS) up to THz frequencies, with a resolution of 1.8 GHz.
XENON is a dark matter direct detection project, consisting of a time projection chamber (TPC) filled with liquid xenon as detection medium. The construction of the next generation detector, XENON1T, is presently taking place at the Laboratori Nazion
ali del Gran Sasso (LNGS) in Italy. It aims at a sensitivity to spin-independent cross sections of $2 cdot 10^{-47} ~ mathrm{cm}^{mathrm{2}}$ for WIMP masses around 50 GeV/c$^{2}$, which requires a background reduction by two orders of magnitude compared to XENON100, the current generation detector. An active system that is able to tag muons and muon-induced backgrounds is critical for this goal. A water Cherenkov detector of $sim$10 m height and diameter has been therefore developed, equipped with 8 inch photomultipliers and cladded by a reflective foil. We present the design and optimization study for this detector, which has been carried out with a series of Monte Carlo simulations. The muon veto will reach very high detection efficiencies for muons ($>99.5%$) and showers of secondary particles from muon interactions in the rock ($>70%$). Similar efficiencies will be obtained for XENONnT, the upgrade of XENON1T, which will later improve the WIMP sensitivity by another order of magnitude. With the Cherenkov water shield studied here, the background from muon-induced neutrons in XENON1T is negligible.
Ultra-high energy neutrinos are detectable through impulsive radio signals generated through interactions in dense media, such as ice. Subsurface in-ice radio arrays are a promising way to advance the observation and measurement of astrophysical high
-energy neutrinos with energies above those discovered by the IceCube detector ($geq$1 PeV) as well as cosmogenic neutrinos created in the GZK process ($geq$100 PeV). Here we describe the $textit{NuPhase}$ detector, which is a compact receiving array of low-gain antennas deployed 185 m deep in glacial ice near the South Pole. Signals from the antennas are digitized and coherently summed into multiple beams to form a low-threshold interferometric phased array trigger for radio impulses. The NuPhase detector was installed at an Askaryan Radio Array (ARA) station during the 2017/18 Austral summer season. $textit{In situ}$ measurements with an impulsive, point-source calibration instrument show a 50% trigger efficiency on impulses with voltage signal-to-noise ratios (SNR) of $le$2.0, a factor of $sim$1.8 improvement in SNR over the standard ARA combinatoric trigger. Hardware-level simulations, validated with $textit{in situ}$ measurements, predict a trigger threshold of an SNR as low as 1.6 for neutrino interactions that are in the far field of the array. With the already-achieved NuPhase trigger performance included in ARASim, a detector simulation for the ARA experiment, we find the trigger-level effective detector volume is increased by a factor of 1.8 at neutrino energies between 10 and 100 PeV compared to the currently used ARA combinatoric trigger. We also discuss an achievable near term path toward lowering the trigger threshold further to an SNR of 1.0, which would increase the effective single-station volume by more than a factor of 3 in the same range of neutrino energies.
The Muon g-2 experiment at Fermilab will measure the anomalous magnetic moment of the muon to a precision of 140 parts per billion, which is a factor of four improvement over the previous E821 measurement at Brookhaven. The experiment will also exten
d the search for the muon electric dipole moment (EDM) by approximately two orders of magnitude. Both of these measurements are made by combining a precise measurement of the 1.45T storage ring magnetic field with an analysis of the modulation of the decay rate of the higher-energy positrons from the (anti-)muon decays recorded by 24 calorimeters and 3 straw tracking detectors. The current status of the experiment as well as results from the initial beam delivery and commissioning run in the summer of 2017 will be discussed.
The Joint Milli-Arcsecond Pathfinder Survey (JMAPS) mission is a Department of Navy (DoN) space-based, all-sky astrometric bright star survey. JMAPS is currently funded for flight, with at 2012 launch date. JMAPS will produce an all-sky astrometric,
photometric and spectroscopic catalog covering the magnitude range of 1-12, with extended results through 15th magnitude at an accuracy of 1 milliarcsecond (mas) positional accuracy at a mean observing epoch of approximately 2013. Using Hipparcos and Tycho positional data from 1991, proper motions with accuracies of 100 microarcseconds (umas) per year should be achievable for all of the brightest stars, with the result that the catalog will degrade at a much reduced rate over time when compared with the Hipparcos catalog. JMAPS will accomplish this with a relatively modest aperture, very high accuracy astrometric telescope flown in low earth orbit (LEO) aboard a microsat. Mission baseline is for a three-year mission life (2012-2015) in a 900 km sun synchronous terminator orbit.
سجل دخول لتتمكن من نشر تعليقات
التعليقات
جاري جلب التعليقات
سجل دخول لتتمكن من متابعة معايير البحث التي قمت باختيارها
