相关论文: Some selected comments on cosmic radioactivities
The time domain of the sky has been only sparsely explored. Nevertheless, recent discoveries from limited surveys and serendipitous discoveries indicate that there is much to be found on timescales from nanoseconds to years and at…
Half-lives of radionuclides span more than 50 orders of magnitude. We characterize the probability distribution of this broad-range data set at the same time that explore a method for fitting power-laws and testing goodness-of-fit. It is…
Variability is a common characteristic of magnetically active stars. Flaring variability is usually interpreted as the observable consequence of transient magnetic reconnection processes happening in the stellar outer atmosphere. Stellar…
The census of heavy elements (metals) produced by all stars through cosmic times up to present-day is limited to ~50%; of these only half are still found within their parent galaxy. The majority of metals is expelled from galaxies into the…
Nearly 50 years ago, the first radio signals from cosmic ray air showers were detected. After many successful studies, however, research ceased not even 10 years later. Only a decade ago, the field was revived with the application of…
Studies in nuclear astrophysics have long been associated with long runs at small accelerators, measuring ever-decreasing cross sections as one approached (but rarely reached) the energy of reactions in stars. But in recent years pioneering…
Modern large-scale astroparticle setups measure high-energy particles, gamma rays, neutrinos, radio waves, and the recently discovered gravitational waves. Ongoing and future experiments are located worldwide. The data acquired have…
The search for the origin of cosmic rays is a quest of almost a hundred years. A recent theoretical proposal gives quantitative predictions, which can be tested with data. Specifically, it has been suggested, that all cosmic rays can be…
Knowledge of the decay rates (or half-lives) of radioisotopes is critical in many fields, including medicine, archeology, and nuclear physics, to name just a few. Central to the many uses of radioisotopes is the belief that decay rates are…
Apparent excesses in early-solar $^{26}$Al, $^{36}$Cl, $^{41}$Ca, and $^{60}$Fe disappear if one accounts for ejecta from massive-star winds concentrated into dense phases of the ISM in star-forming regions. The removal of apparent excesses…
For the better part of a century the field of nuclear astrophysics has aimed to answer fundamental questions about nature, such as the origin of the elements and the behavior of high-density, low-temperature matter. Sustained and concerted…
The nuclear $\gamma$-ray lines in the MeV range of the electromagnetic spectrum hold a vast variety of astrophysical, particle-physical, and fundamental physical information that is otherwise extreme difficult to access. MeV $\gamma$-ray…
The study of the formation of massive stars presents complex challenges from both theoretical and observational points of view. The initial phases of evolution, for instance, remain almost hidden except at radio and IR wavelengths. In this…
Cosmic rays (CRs) generate diffuse emission while interacting with the Galactic magnetic field (B-field), the interstellar gas and the radiation field. This diffuse emission extends from radio, microwaves, through X-rays, to high-energy…
Most of the visible matter in the Universe is ionized, so that cosmic magnetic fields are quite easy to generate and due to the lack of magnetic monopoles hard to destroy. Magnetic fields have been measured in or around practically all…
Our Sun, like all stars, formed within a cold molecular cloud. Astronomical observations and theory provide considerable detail into this process. Yet cosmochemical observations of short lived radionuclides in primitive meteorites, in…
Gamma-ray bursts (GRBs) are extremely energetic events at cosmological distances. They provide unique laboratory to investigate fundamental physical processes under extreme conditions. Due to extreme luminosities, GRBs are detectable at…
Stars are fossils that retain the history of their host galaxies. Elements heavier than helium are created inside stars and are ejected when they die. From the spatial distribution of elements in galaxies, it is therefore possible to…
This paper summarizes the three-day international workshop "Radio Stars and Their Lives in the Galaxy", held at the Massachusetts Institute of Technology Haystack Observatory on 2012 October 3-5. The workshop was organized to provide a…
Motivated by the discovery of a number of radio relics we investigate the fate of fossil radio plasma during a merger of clusters of galaxies using cosmological smoothed-particle hydrodynamics simulations. Radio relics are extended,…