We analyze the modification of the constraint curve due to the variation of the fraction of local dark matter belonging to the stream.
#Waves complete v9r28 series#
Such curve is then analyzed in detail showing the magnitude of the contribution of the first-order and second-order terms of the signal series expansion.
In case of no detection a limit curve for the coupling parameter d*g is derived.
Special attention is paid to the second-order term of the signal approximate series expansion whose contribution ends up to be not negligible when one factors in the specific geometrical dimensions and frequency range of gravitational waves detectors like Advanced LIGO and Advanced Virgo.As suggested by recent surveys, we assume the presence of a dark matter stream in the local neighborhood of the solar system and show its effect on the signal.We then propose and discuss a hierarchical statistical analysis aimed to the signal detection. We derive and discuss the signal produced by this interaction through different approaches deriving both approximated and exact solutions. In the last decades several hypothesis, such as the WIMPs model, have been proposed to solve such puzzle but none of them has been able so farto succeed.In this thesis work we will focus on an other very appealing model in which dark matter is successfully described by an ultra-light scalar field whose origin can be sought in the low-energy limit of one of the most promising unification theories: the String Theory.In this work we show how such scalar field, if present, interacts with standard matter and in particular with the optical apparatus that is at the core of gravitational waves antennas. The existence of the dark matter and the truth beyond its nature has been one of the greatest puzzle of the twentieth century and still it is nowadays. In the latter case our results are compatible with the upper limits from the Galactic halo analysis reported by the Fermi-LAT collaboration for the case in which the same conservative approach without modeling of the astrophysical background is employed. The upper limits on the annihilation cross section of dark matter particles obtained are two orders of magnitude stronger than without contraction. For the μ+μ� channel, where the e↵ect of the inverse Compton scattering is important, depending on models of the Galactic magnetic field the exclusion of the thermal cross-section is for a WIMP mass smaller than about 150 to 400 GeV. In particular, we find that for b ̄b and ⌧+⌧� or W+W� dark matter annihilation channels, the upper limits on the annihila- tion cross section imply that the thermal cross section is excluded for a Weakly Interacting Massive Particle (WIMP) mass smaller than about 700 and 500GeV, respectively. The constraints obtained in the likely case that the collapse of baryons to the Galactic Center is accompa- nied by the contraction of the dark matter are strong.
Our analysis is conservative since it simply requires that the expected dark matter signal does not exceed the observed emission. We derive constraints on parameters of generic dark matter candidates by com- paring theoretical predictions with the gamma-ray emission observed by the Fermi-LAT from the region around the Galactic Center.
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