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A large fraction of stars form within young embedded clusters, and these environments produce a substantial ultraviolet (UV) background radiation field, which can provide feedback on the star formation process. To assess the possible effects of young stellar clusters on the formation of their constituent stars and planets, this paper constructs the expected radiation fields produced by these clusters. We include both the observed distribution of cluster sizes $N$ in the solar neighborhood and an extended distribution that includes clusters with larger $N$. The paper presents distributions of the FUV and EUV luminosities for clusters with given stellar membership $N$, distributions of FUV and EUV luminosity convolved over the expected distribution of cluster sizes $N$, and the corresponding distributions of FUV and EUV fluxes. These flux distributions are calculated both with and without the effects of extinction. Finally, we consider the effects of variations in the stellar initial mass function on these radiation fields. Taken together, these results specify the distributions of radiation environments that forming solar systems are expected to experience.
We investigate the quantum radiation produced by an Unruh-De Witt detector in a uniformly accelerating motion coupled to the vacuum fluctuations. Quantum radiation is nonvanishing, which is consistent with the previous calculation by Lin and Hu [Phys
We propose a simple experiment to explore magnetic fields created by electric railways and compare them with a simple model and parameters estimated using easily available information. A pedestrian walking on an overpass above train tracks registers
Aims. We are trying to probe conditions in the youngest super star clusters, those still embedded in dense obscuring clouds. Methods. The hydrogen recombination lines in the radio and infrared can be observed through the obscuration, as the optical a
We study the evolution of embedded clusters. The equations of motion of the stars in the cluster are solved by direct N-body integration while taking the effects of stellar evolution and the hydrodynamics of the natal gas content into account. The gr
We report on the discovery of several compact regions of mid-infrared emission in the starforming circum nuclear disk of the starburst/Seyfert2 galaxy NGC7582. The compact sources do not have counterparts in the optical and near-infrared, suggesting