Many models of physics beyond the standard model predict the existence of new Abelian forces with new gauge bosons mediating interactions between "dark sectors" and the standard model. We report a ...search for a dark boson Z' coupling only to the second and third generations of leptons in the reaction e super(+) e super(?)arrowrightmu super(+)mu super(?)Z',Z'arrowrightmu super(+) mu? using 514fb super(?1) of data collected by the BABAR experiment. No significant signal is observed for Z' masses in the range 0.212-10 GeV. Limits on the coupling parameter g' as low as 7x10 super(?4) are derived, leading to improvements in the bounds compared to those previously derived from neutrino experiments.
Abstract
We have developed and tested a direct-sampling RF receiver
capable of measuring the amplitude of a 1497 MHz sinusoidal beam
signal in 0.5 ms integration windows with a relative uncertainty ...of
better than 10 parts per million. The receiver is intended for
measuring signals from beam current monitoring cavities on the
beamline of the Continuous Electron Beam Accelerator Facility
(CEBAF) at Jefferson Lab. The beam signal strength, frequency, and
integration window fulfill the thus far unmet requirements of the
upcoming MOLLER experiment to measure the beam charge for different
helicity states.
Optimization of the first CUPID detector module Augier, C.; Balata, M.; Barabash, A. S. ...
The European physical journal. C, Particles and fields,
09/2022, Letnik:
82, Številka:
9
Journal Article
Recenzirano
Odprti dostop
CUPID will be a next generation experiment searching for the neutrinoless double
β
decay, whose discovery would establish the Majorana nature of the neutrino. Based on the experience achieved with ...the CUORE experiment, presently taking data at LNGS, CUPID aims to reach a background free environment by means of scintillating Li
2
100
MoO
4
crystals coupled to light detectors. Indeed, the simultaneous heat and light detection allows us to reject the dominant background of
α
particles, as proven by the CUPID-0 and CUPID-Mo demonstrators. In this work we present the results of the first test of the CUPID baseline module. In particular, we propose a new optimized detector structure and light sensors design to enhance the engineering and the light collection, respectively. We characterized the heat detectors, achieving an energy resolution of (5.9 ± 0.2) keV FWHM at the
Q
-value of
100
Mo (about 3034 keV). We studied the light collection of the baseline CUPID design with respect to an alternative configuration which features gravity-assisted light detectors’ mounting. In both cases we obtained an improvement in the light collection with respect to past measures and we validated the particle identification capability of the detector, which ensures an
α
particle rejection higher than 99.9%, fully satisfying the requirements for CUPID.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Conventional CMOS technology operated in cryogenic conditions has recently attracted interest for its use in low-noise electronics. We present one of the first characterizations of 180 nm CMOS ...technology at a temperature of 100 mK, extracting I/V characteristics, threshold voltages, and transconductance values, as well as observing their temperature dependence. We find that CMOS devices remain fully operational down to these temperatures, although we observe hysteresis effects in some devices. The measurements described in this paper can be used to inform the future design of CMOS devices intended to be operated in this deep cryogenic regime.
CUORE—the Cryogenic Underground Observatory for Rare Events—is an experiment searching for the neutrinoless double-beta (0νββ) decay of 130Te with an array of 988 TeO2 crystals operated as bolometers ...at ∼10 mK in a large dilution refrigerator. With this detector, we aim for a 130Te 0νββ decay half-life sensitivity of 9×1025 y with 5 y of live time, and a background index of ≲10−2 counts/keV/kg/y. Making an effort to maintain radiopurity by minimizing the bolometers' exposure to radon gas during their installation in the cryostat, we perform all operations inside a dedicated cleanroom environment with a controlled radon-reduced atmosphere. In this paper, we discuss the design and performance of the CUORE Radon Abatement System and cleanroom, as well as a system to monitor the radon level in real time.
CUPID is a next-generation neutrinoless double-β decay experiment that will require cryogenic light detectors to improve background suppression, via the simultaneous readout of heat and light ...channels from its scintillating crystals. In this work, we showcase light detectors based on an alternative Ir-Pt bilayer transition-edge sensor. We have performed a systematic study to improve the thermal coupling between the photon absorber and the sensor, and thereby its responsivity. Our first devices meet CUPID's baseline noise requirement of < 100 eV rms. Our detectors have risetimes of approximately 180μs and measured timing jitter of < 20μs for the expected signal to noise at the Q value of the decay, which achieves the CUPID's criterion of rejecting two-neutrino double-β decay pile-up events. In conclusion, the current work will inform the fabrication of future devices, culminating in the final TES design and a scaleable readout scheme for CUPID.
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