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Related papers: Demography of galactic technosignatures

200 papers

How long a technological civilization remains active, and what determines whether it collapses or persists, is a central question for both projecting humanity's future and assessing the prevalence of detectable intelligence in the galaxy.…

Physics and Society · Physics 2026-04-16 Celia Blanco , Jacob Haqq-Misra , George Profitiliotis

We address the possibility that intelligent civilisations that destroy themselves could present signatures observable by humanity. Placing limits on the number of self-destroyed civilisations in the Milky Way has strong implications for the…

Earth and Planetary Astrophysics · Physics 2020-12-16 Adam Stevens , Duncan Forgan , Jack O'Malley-James

High-energy gamma rays of interstellar origin are produced by the interaction of cosmic-ray (CR) particles with the diffuse gas and radiation fields in the Galaxy. The main features of this emission are well understood and are reproduced by…

High Energy Astrophysical Phenomena · Physics 2017-09-06 Troy A. Porter , Gudlaugur Johannesson , Igor V. Moskalenko

We investigate the environmental dependence of stellar population properties of galaxies in the local universe. Physical quantities related to the stellar content of galaxies are derived from a spectral synthesis method applied to a…

Astrophysics · Physics 2009-09-29 A. Mateus , Laerte Sodre , Roberto Cid Fernandes , Grazyna Stasinska

We study the statistical properties of the combined emission of a population of discrete sources (e.g. X-ray emission of a galaxy due to its X-ray binaries population). Namely, we consider the dependence of their total luminosity…

Astrophysics · Physics 2009-11-10 M. Gilfanov , H-J. Grimm , R. Sunyaev

Nitrogen dioxide (NO$_2$) on Earth today has biogenic and anthropogenic sources. During the COVID-19 pandemic, observations of global NO$_2$ emissions have shown significant decrease in urban areas. Drawing upon this example of NO$_2$ as an…

Earth and Planetary Astrophysics · Physics 2021-03-03 Ravi Kopparapu , Giada Arney , Jacob Haqq-Misra , Jacob Lustig-Yaeger , Geronimo Villanueva

Pulsars are highly magnetized rotating neutron stars, emitting in a broad electromagnetic energy range. Reproducing the observed pulsars population refines our understanding of their formation and evolution scenarios as well as their…

High Energy Astrophysical Phenomena · Physics 2024-11-27 Mattéo Sautron , Jérôme Pétri , Dipanjan Mitra , Ludmilla Dirson

Elemental abundance ratios as tracers of stellar populations are discussed with emphasis on F, G, and K stars providing a `fossil' record of the chemical evolution of the Galaxy. Most abundance studies have been based on homogeneous 1D…

Astrophysics of Galaxies · Physics 2011-09-20 Poul Erik Nissen

Global Climate Models (GCMs) provide forecasts of future climate warming using a wide variety of highly sophisticated anthropogenic CO2 emissions models as input, each based on the evolution of four emissions "drivers": population p,…

Atmospheric and Oceanic Physics · Physics 2011-04-06 Timothy J. Garrett

Galaxy surveys targeting emission lines are characterising the evolution of star-forming galaxies, but there is still little theoretical progress in modelling their physical properties. We predict nebular emission from star-forming galaxies…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Alvaro Orsi , Nelson Padilla , Brent Groves , Sofia Cora , Tomas Tecce , Ignacio Gargiulo , Andres Ruiz

The existence of multiple regions of space beyond the observable Universe (within the so-called "multiverse") where the vacuum energy density takes different values, has been postulated as an explanation for the low non-zero value observed…

Astrophysics · Physics 2009-11-11 Abraham Loeb

The Galactic diffuse emission (GDE) is formed when cosmic rays leave the sources where they were accelerated, diffusively propagate in the Galactic magnetic field, and interact with the interstellar medium and interstellar radiation field.…

High Energy Astrophysical Phenomena · Physics 2023-11-28 Ke Fang , John S. Gallagher , Francis Halzen

Estimates of galaxy distances based on indicators that are independent of cosmological redshift are fundamental to astrophysics. Researchers use them to establish the extragalactic distance scale, to underpin estimates of the Hubble…

Cosmic rays (CRs) in the Galaxy are an important dynamical component of the interstellar medium (ISM) that interact with the other major components (interstellar magnetic and radiation fields, and gas) to produce broadband interstellar…

High Energy Astrophysical Phenomena · Physics 2020-01-08 Troy A. Porter , Gudlaugur Johannesson , Igor V. Moskalenko

The probability of detecting technosignatures (i.e. evidence of technological activity beyond Earth) increases with their longevity, or the time interval over which they manifest. Therefore, the assumed distribution of longevities has some…

Popular Physics · Physics 2024-05-02 A. Balbi , C. Grimaldi

The path length distribution of Galactic cosmic rays (GCRs) is the fundamental ingredient for modeling the propagation process of GCRs based on the so-called weighted slab method. We try to derive this distribution numerically by taking…

High Energy Astrophysical Phenomena · Physics 2015-01-14 S. Miyake , H. Muraishi , S. Yanagita

The population of young, non-recycled pulsars with spin down energies Edot >10^35 erg/s is sampled predominantly at gamma-ray and radio wavelengths. A total of 137 such pulsars are known, with partial overlap between the sources detectable…

High Energy Astrophysical Phenomena · Physics 2020-07-29 Simon Johnston , D. A. Smith , A. Karastergiou , M. Kramer

The cosmic ray energy spectra encode very important information about the mechanisms that generate relativistic particles in the Milky Way, and about the properties of the Galaxy that control their propagation. Relativistic electrons and…

High Energy Astrophysical Phenomena · Physics 2019-02-20 Paolo Lipari

In this paper we consider the extent to which a lack of observations from SETI may be used to quantify the Fermi paradox. Building on previous research, we construct a geometrical model to compute the probability of at least one detection…

Instrumentation and Methods for Astrophysics · Physics 2025-12-29 Matthew Civiletti

We investigated the habitability of the Milky Way, making use of recent observational analysis on the prevalence of Earth-sized planets, in order to estimate where and when potentially habitable star systems may have formed over the course…

Astrophysics of Galaxies · Physics 2015-09-10 Daniel Legassick