Next Issue
Volume 5, March
Previous Issue
Volume 4, September
 
 

Particles, Volume 4, Issue 4 (December 2021) – 6 articles

Cover Story (view full-size image): P-type point contact (PPC) germanium detectors are used in rare event and low-background searches, including neutrinoless double beta decay, low-energy dark matter, and coherent elastic neutrino-nucleus scattering. The detectors feature an excellent energy resolution, low detection thresholds, and enhanced background rejection capabilities. However, due to their large, passivated surface, separating the signal readout contact from the bias voltage electrode, PPC detectors are susceptible to surface effects. A profound understanding of these effects is essential to estimate the impact of surface backgrounds on low-background searches. In this work, the response of a PPC detector to alpha and beta particles hitting the passivated surface was studied in detail. View this paper
  • Issues are regarded as officially published after their release is announced to the table of contents alert mailing list.
  • You may sign up for e-mail alerts to receive table of contents of newly released issues.
  • PDF is the official format for papers published in both, html and pdf forms. To view the papers in pdf format, click on the "PDF Full-text" link, and use the free Adobe Reader to open them.
Order results
Result details
Select all
Export citation of selected articles as:
41 pages, 746 KiB  
Article
The Relation between General Relativity’s Metrics and Special Relativity’s Gravitational Scalar Generalized Potentials and Case Studies on the Schwarzschild Metric, Teleparallel Gravity, and Newtonian Potential
by Spyridon Vossos, Elias Vossos and Christos G. Massouros
Particles 2021, 4(4), 536-576; https://0-doi-org.brum.beds.ac.uk/10.3390/particles4040039 - 08 Dec 2021
Cited by 1 | Viewed by 2656
Abstract
This paper shows that gravitational results of general relativity (GR) can be reached by using special relativity (SR) via a SR Lagrangian that derives from the corresponding GR time dilation and vice versa. It also presents a new SR gravitational central scalar generalized [...] Read more.
This paper shows that gravitational results of general relativity (GR) can be reached by using special relativity (SR) via a SR Lagrangian that derives from the corresponding GR time dilation and vice versa. It also presents a new SR gravitational central scalar generalized potential V=V(r,r.,ϕ.), where r is the distance from the center of gravity and r.,ϕ. are the radial and angular velocity, respectively. This is associated with the Schwarzschild GR time dilation from where a SR scalar generalized potential is obtained, which is exactly equivalent to the Schwarzschild metric. Thus, the Precession of Mercury’s Perihelion, the Gravitational Deflection of Light, the Shapiro time delay, the Gravitational Red Shift, etc., are explained with the use of SR only. The techniques used in this paper can be applied to any GR spacetime metric, Teleparallel Gravity, etc., in order to obtain the corresponding SR gravitational scalar generalized potential and vice versa. Thus, the case study of Newtonian Gravitational Potential according to SR leads to the corresponding non-Riemannian metric of GR. Finally, it is shown that the mainstream consideration of the Gravitational Red Shift contains two approximations, which are valid in weak gravitational fields only. Full article
Show Figures

Figure 1

15 pages, 456 KiB  
Article
Beta Decay in Medium-Mass Nuclei with the In-Medium Similarity Renormalization Group
by Steven Ragnar Stroberg
Particles 2021, 4(4), 521-535; https://0-doi-org.brum.beds.ac.uk/10.3390/particles4040038 - 18 Nov 2021
Cited by 4 | Viewed by 2684
Abstract
We review the status of ab initio calculations of allowed beta decays (both Fermi and Gamow–Teller), within the framework of the valence-space in-medium similarity renormalization group approach. Full article
(This article belongs to the Special Issue Beta-Decay Processes in Nuclear Systems)
Show Figures

Figure 1

9 pages, 331 KiB  
Communication
Azimuthal Correlations of D Mesons with Charged Particles in Simulations with the ALICE Experiment
by Eszter Frajna and Robert Vertesi
Particles 2021, 4(4), 512-520; https://0-doi-org.brum.beds.ac.uk/10.3390/particles4040037 - 01 Nov 2021
Viewed by 2310
Abstract
In this work, we present the results of a component-level analysis with Monte Carlo simulations, which aid the interpretation of recent ALICE results of the azimutal correlation distribution of prompt D mesons with charged hadrons in pp and p–Pb collisions at sNN [...] Read more.
In this work, we present the results of a component-level analysis with Monte Carlo simulations, which aid the interpretation of recent ALICE results of the azimutal correlation distribution of prompt D mesons with charged hadrons in pp and p–Pb collisions at sNN = 5.02 TeV. Parton-level contributions and fragmentation properties are evaluated. Charm and beauty contributions are compared in order to identify the observables that serve as sensitive probes of the production and hadronisation of heavy quarks. Full article
(This article belongs to the Collection High Energy Physics)
Show Figures

Figure 1

23 pages, 2275 KiB  
Article
Surface Characterization of P-Type Point Contact Germanium Detectors
by Frank Edzards, Lukas Hauertmann, Iris Abt, Chris Gooch, Björn Lehnert, Xiang Liu, Susanne Mertens, David C. Radford, Oliver Schulz and Michael Willers
Particles 2021, 4(4), 489-511; https://0-doi-org.brum.beds.ac.uk/10.3390/particles4040036 - 20 Oct 2021
Cited by 3 | Viewed by 2929
Abstract
P-type point contact (PPC) germanium detectors are used in rare event and low-background searches, including neutrinoless double beta (0νββ) decay, low-energy nuclear recoils, and coherent elastic neutrino-nucleus scattering. The detectors feature an excellent energy resolution, low detection thresholds down to the sub-keV range, [...] Read more.
P-type point contact (PPC) germanium detectors are used in rare event and low-background searches, including neutrinoless double beta (0νββ) decay, low-energy nuclear recoils, and coherent elastic neutrino-nucleus scattering. The detectors feature an excellent energy resolution, low detection thresholds down to the sub-keV range, and enhanced background rejection capabilities. However, due to their large passivated surface, separating the signal readout contact from the bias voltage electrode, PPC detectors are susceptible to surface effects such as charge build-up. A profound understanding of their response to surface events is essential. In this work, the response of a PPC detector to alpha and beta particles hitting the passivated surface was investigated in a multi-purpose scanning test stand. It is shown that the passivated surface can accumulate charges resulting in a radial-dependent degradation of the observed event energy. In addition, it is demonstrated that the pulse shapes of surface alpha events show characteristic features which can be used to discriminate against these events. Full article
(This article belongs to the Special Issue High Purity Germanium Detectors)
Show Figures

Figure 1

21 pages, 555 KiB  
Article
Quantization of Gravity and Finite Temperature Effects
by I. Y. Park
Particles 2021, 4(4), 468-488; https://0-doi-org.brum.beds.ac.uk/10.3390/particles4040035 - 14 Oct 2021
Cited by 3 | Viewed by 2237
Abstract
Gravity is perturbatively renormalizable for the physical states which can be conveniently defined via foliation-based quantization. In recent sequels, one-loop analysis was explicitly carried out for Einstein-scalar and Einstein-Maxwell systems. Various germane issues and all-loop renormalizability have been addressed. In the present work [...] Read more.
Gravity is perturbatively renormalizable for the physical states which can be conveniently defined via foliation-based quantization. In recent sequels, one-loop analysis was explicitly carried out for Einstein-scalar and Einstein-Maxwell systems. Various germane issues and all-loop renormalizability have been addressed. In the present work we make further progress by carrying out several additional tasks. Firstly, we present an alternative 4D-covariant derivation of the physical state condition by examining gauge choice-independence of a scattering amplitude. To this end, a careful dichotomy between the ordinary, and large gauge symmetries is required and appropriate gauge-fixing of the ordinary symmetry must be performed. Secondly, vacuum energy is analyzed in a finite-temperature setup. A variant optimal perturbation theory is implemented to two-loop. The renormalized mass determined by the optimal perturbation theory turns out to be on the order of the temperature, allowing one to avoid the cosmological constant problem. The third task that we take up is examination of the possibility of asymptotic freedom in finite-temperature quantum electrodynamics. In spite of the debates in the literature, the idea remains reasonable. Full article
Show Figures

Figure 1

71 pages, 2928 KiB  
Review
Radiative Corrections to Semileptonic Beta Decays: Progress and Challenges
by Chien-Yeah Seng
Particles 2021, 4(4), 397-467; https://0-doi-org.brum.beds.ac.uk/10.3390/particles4040034 - 28 Sep 2021
Cited by 14 | Viewed by 2991
Abstract
We review some recent progress in the theory of electroweak radiative corrections in semileptonic decay processes. The resurrection of the so-called Sirlin’s representation based on current algebra relations permits a clear separation between the perturbatively-calculable and incalculable pieces in the [...] Read more.
We review some recent progress in the theory of electroweak radiative corrections in semileptonic decay processes. The resurrection of the so-called Sirlin’s representation based on current algebra relations permits a clear separation between the perturbatively-calculable and incalculable pieces in the O(GFα) radiative corrections. The latter are expressed as compact hadronic matrix elements that allow systematic non-perturbative analysis such as dispersion relation and lattice QCD. This brings substantial improvements to the precision of the electroweak radiative corrections in semileptonic decays of pion, kaon, free neutron and JP=0+ nuclei that are important theory inputs in precision tests of the Standard Model. Unresolved issues and future prospects are discussed. Full article
(This article belongs to the Special Issue Beta-Decay Processes in Nuclear Systems)
Show Figures

Figure 1

Previous Issue
Next Issue
Back to TopTop