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We present a new value for the neutron lifetime of 878.5 +- 0.7 stat. +- 0.3 syst. This result differs from the world average value (885.7 +- 0.8 s) by 6.5 standard deviations and by 5.6 standard deviations from the previous most precise…

Recent experimental studies of the antiproton-deuteron system at low energies have shown that the imaginary part of the antiproton-deuteron scattering length is smaller than the antiproton-proton one. Two- and three-body systems with strong…

Nuclear Theory · Physics 2016-09-08 V. A. Karmanov , K. V. Protasov , A. Yu. Voronin

In this work, we explore constraints on the emergence and longevity of technologically intelligent civilizations in our Galaxy, considering the Fermi paradox. We argue that under optimistic assumptions about the probability of life and…

Astrophysics of Galaxies · Physics 2026-02-27 Sohrab Rahvar , Shahin Rouhani

We discuss problems with some observational estimates indicating long protostellar core lifetimes and large stellar age spreads in molecular clouds. We also point out some additional observational constraints which suggest that protostellar…

Astrophysics · Physics 2007-05-23 Javier Ballesteros-Paredes , Lee Hartmann

We present results of a search for proton decays, $p \to \bar{\nu} K^+$, using data from a 33 kton$\cdot$year exposure of the Super-Kamiokande detector. Two decay modes of the kaon, $K^+ \to \mu^+ \nu_{\mu}$ and $K^+ \to \pi^+ \pi^0$, were…

High Energy Physics - Experiment · Physics 2012-08-27 Kamiokande Collaboration , Y. Hayato , M. Earl

The lifetime of protoplanetary disks is a crucial parameter for planet formation research. Observations of disk fractions in star clusters imply median disk lifetimes of 1 -- 3 Myr. This very short disk lifetime calls for planet formation…

Astrophysics of Galaxies · Physics 2022-10-06 Susanne Pfalzner , Shahrzad Dehghani , Arnaud Michel

We argue that the event-by-event fluctuation of the proton number is a meaningful and promising observable for the purpose of detecting the QCD critical end-point in heavy-ion collision experiments. The long range fluctuation of the order…

High Energy Physics - Phenomenology · Physics 2009-11-10 Y. Hatta , M. A. Stephanov

Recent evidence appears to confirm that the ultra-high-energy primary cosmic ray spectrum consists mostly of protons. The fact that these protons can traverse large distances to reach Earth allows us to place bounds on Lorentz violations.…

High Energy Physics - Phenomenology · Physics 2008-11-26 Brett Altschul

The expected proton and neutrino fluxes from decays of massive metastable relic particles is calculated using the HERWIG QCD event generator. The predicted proton spectrum can account for the observed flux of extremely high energy cosmic…

High Energy Physics - Phenomenology · Physics 2011-02-16 Michael Birkel , Subir Sarkar

Relativistic time dilation implies that an accelerating excited atom would have its lifetime prolonged in the lab frame. In this paper, we demonstrate a complementary effect: Longer-lived excited atoms turn out to have been accelerated. We…

Quantum Physics · Physics 2025-11-11 Yakov Bloch , Avshalom C. Elitzur

We study the leptonic decay of charged pions in a compact star environment. Considering leptons as a degenerated Fermi system, pions are tightly constrained to decay into these particles because their Fermi levels are occupied. Thus, pion…

High Energy Physics - Phenomenology · Physics 2017-06-07 Marcelo Loewe , Alfredo Raya , Cristian Villavicencio

If strange matter is absolutely stable, the ordinary nuclei decay to strangelets, while neutron stars convert into strange stars. Lifetimes of the ordinary nuclei are constrained experimentally to be above $\sim 10^{33}$ years, while…

High Energy Astrophysical Phenomena · Physics 2015-03-05 M. I. Krivoruchenko , B. V. Martemyanov

Is life most likely to emerge at the present cosmic time near a star like the Sun? We address this question by calculating the relative formation probability per unit time of habitable Earth-like planets within a fixed comoving volume of…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-31 Abraham Loeb , Rafael A. Batista , David Sloan

Our experiment using gravitationally trapped ultracold neutrons (UCN) to measure the neutron lifetime is reviewed. Ultracold neutrons were trapped in a material bottle covered with perfluoropolyether. The neutron lifetime was deduced from…

The bulk of observed ultrahigh energy cosmic rays could be light or heavier elements, and originate from an either steady or transient population of sources. This leaves us with four general categories of sources. Energetic requirements set…

High Energy Astrophysical Phenomena · Physics 2016-11-21 Ke Fang , Kumiko Kotera

Environmental effects on the muon lifetime are described. A general theorem on the cancellation of bound state phase space suppression and final state interaction enhancement is illustrated for muonium and muonic atoms. Lessons from those…

High Energy Physics - Phenomenology · Physics 2007-05-23 William J. Marciano

The neutron lifetime is important in understanding the production of light nuclei in the first minutes after the big bang and it provides basic information on the charged weak current of the standard model of particle physics. Two different…

An alternative to the current accepted model of expanding universe is presented. The proposal is anchored in the objective realist, stochastic formulation of quantum mechanics wherein the Planck constant plays the role of a diffusion…

General Physics · Physics 2014-02-18 R. Ramanathan

The article provides a theoretical substantiation for a significant increase in the level of accuracy in determining the neutron lifetime using an alternative concept of neutron beta decay. Neutrons are distributed among different subsets…

Nuclear Theory · Physics 2023-08-03 V. V. Vasiliev

The precise value of the mean neutron lifetime, $\tau_n$, plays an important role in nuclear and particle physics and cosmology. It is a key input for predicting the ratio of protons to helium atoms in the primordial universe and is used to…

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