3,216 research outputs found

    Warfighting for cyber deterrence: a strategic and moral imperative

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    Theories of cyber deterrence are developing rapidly. However, the literature is missing an important ingredient—warfighting for deterrence. This controversial idea, most commonly associated with nuclear strategy during the later stages of the Cold War, affords a number of advantages. It provides enhanced credibility for deterrence, offers means to deal with deterrence failure (including intrawar deterrence and damage limitation), improves compliance with the requirements of just war and ultimately ensures that strategy continues to function in the post-deterrence environment. This paper assesses whether a warfighting for deterrence approach is suitable for the cyber domain. In doing so, it challenges the notion that warfighting concepts are unsuitable for operations in cyberspace. To do this, the work constructs a conceptual framework that is then applied to cyber deterrence. It is found that all of the advantages of taking a warfighting stance apply to cyber operations. The paper concludes by constructing a warfighting model for cyber deterrence. This model includes passive and active defences and cross-domain offensive capabilities. The central message of the paper is that a theory of victory (strategy) must guide the development of cyber deterrence

    Resolution of the Compact Radio Continuum Sources in Arp220

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    We present 2 cm and 3.6 cm wavelength very long baseline interferometry images of the compact radio continuum sources in the nearby ultra-luminous infrared galaxy Arp220. Based on their radio spectra and variability properties, we confirm these sources to be a mixture of supernovae (SNe) and supernova remnants (SNRs). Of the 17 detected sources we resolve 7 at both wavelengths. The SNe generally only have upper size limits. In contrast all the SNRs are resolved with diameters {\geq} 0.27 pc. This size limit is consistent with them having just entered their Sedov phase while embedded in an interstellar medium (ISM) of density 10^4 cm^{-3} . These objects lie on the diameter-luminosity correlation for SNRs (and so also on the diameter-surface brightness relation) and extend these correlations to very small sources. The data are consistent with the relation L {\propto} D^{-9/4}. Revised equipartition arguments adjusted to a magnetic field to relativistic particle energy density ratio of 1% combined with a reasonable synchrotron-emitting volume filling factor of 10% give estimated magnetic field strengths in the SNR shells of ~ 15-50 mG. The SNR shell magnetic fields are unlikely to come from compression of ambient ISM fields and must instead be internally generated. We set an upper limit of 7 mG for the ISM magnetic field. The estimated energy in relativistic particles, 2%-20% of the explosion kinetic energy, is consistent with estimates from models that fit the IR-radio correlation in compact starburst galaxies.Comment: 16 pages, 5 figure

    On the origin of the 40-120 micron emission of galaxy disks: A comparison with H-alpha fluxes

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    A comparison of 40 to 120 micron Infrared Astronomy Satellite (IRAS) fluxes with published H alpha and UBV photometry shows that the far infrared emission of galaxy disks consists of at least two components: a warm one associated with OB stars in HII-regions and young star-forming complexes, and a cooler one from dust in the diffuse, neutral interstellar medium, heated by the more general interstellar radiation field of the old disk population (a cirrus-like component). Most spiral galaxies are dominated by emission from the cooler component in this model. A significant fraction of the power for the cool component must originate with non-ionizing stars. For a normal spiral disk there is a substantial uncertainty in a star formation rate derived using either the H alpha or the far infrared luminosity

    Radio imaging of core-dominated high redshift quasars

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    VLA imaging at kiloparsec-scale resolution of sixteen core-dominated radio-loud QSOs is presented. Many objects appear to display variable radio emission and their radio morphologies are significantly smaller than those of steep-spectrum quasars, consistent with these objects being observed at sight lines close to their (relativistic, γ≈\gamma \approx 4-7) jet axes. The usefulness of the radio source orientation indicator R_V, being defined as ratio of radio core and rest frame optical V-band luminosity, is confirmed.Comment: 11 pages, 11 postscript figures, uses aa.cls 4.03 for LaTeX2e To appear in Astronomy and Astrophysic

    Asymmetric Dark Matter and the hadronic spectra of hidden QCD

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    The idea that dark matter may be a composite state of a hidden nonabelian gauge sector has received great attention in recent years. Frameworks such as asymmetric dark matter motivate the idea that dark matter may have similar mass to the proton, while mirror matter and G×GG \times G grand unified theories provide rationales for additional gauge sectors which may have minimal interactions with standard model particles. In this work we explore the hadronic spectra that these dark QCD models can allow. The effects of the number of light colored particles and the value of the confinement scale on the lightest stable state, the dark matter candidate, are examined in the hyperspherical constituent quark model for baryonic and mesonic states.Comment: 22 pages, 11 figures. Additional discussion, matches published versio

    Britain's emerging cyber-strategy

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    © RUSI JOURNAL AUGUST/SEPTEMBER 2016. In recent years, cyber-power has attracted a great deal of attention in government strategy and security reviews. This has been matched by regular increases in budget and the establishment of new organisations to co-ordinate UK activity in cyberspace. The result is the emergence of UK cyber-strategy. However, David J Lonsdale argues that at present UK cyber-strategy is not comprehensive, nor does it cohesively bring together the different elements of cyber-power to effectively serve UK policy objectives. Here, he identifies the components of the UK’s emerging cyber-strategy and assesses the UK’s approach against a comprehensive cyber-strategy framework. The latter includes seven elements: defence; cyber-espionage; information manipulation; widespread disruptive attacks; raids; joint operations; and deterrence
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