Experimental investigation and monitoring of a polypropylene-based fiber reinforced concrete road pavement

Abstract In this work, basic guidelines are provided for the design of a polypropylene-based fiber reinforced concrete (PFRC) road pavement, as applied in an actual testing section resting inside a tunnel of the "Quadrilatero Marche-Umbria" road empowerment project, Italy. Results of a six-month monitoring carried out on actual traffic loads are also presented, as a feedback to the designing stage. Monitoring encompasses direct measurement of the strain level inside the cast as well as acoustic measurement. It is shown that the fiber reinforced concrete technology provides an efficient, safe as well as cost-effective design solution for roadways, especially inside tunnels

Magnetar outbursts: an observational review

Transient outbursts from magnetars have shown to be a key property of their emission, and one of the main way to discover new sources of this class. From the discovery of the first transient event around 2003, we now count about a dozen of outbursts, which increased the number of these strongly magnetic neutron stars by a third in six years. Magnetar outbursts might involve their multi-band emission resulting in an increased activity from radio to hard X-ray, usually with a soft X-ray flux increasing by a factor of 10-1000 with respect to the quiescent level. A connected X-ray spectral evolution is also often observed, with a spectral softening during the outburst decay. The flux decay times vary a lot from source to source, ranging from a few weeks to several years, as also the decay law which can be exponential-like, a power-law or even multiple power-laws can be required to model the flux decrease. We review here on the latest observational results on the multi-band emission of magnetars, and summarize one by one all the transient events which could be studied to date from these sources.Comment: 34 pages, 6 figures. Chapter of the Springer Book ASSP 7395 "High-energy emission from pulsars and their systems", proceeding of the Sant Cugat Forum on Astrophysics (12-16 April 2010). Review updated to January 201

New Upper Limit of Terrestrial Equivalence Principle Test for Rotating Extended Bodies

Improved terrestrial experiment to test the equivalence principle for rotating extended bodies is presented, and a new upper limit for the violation of the equivalence principle is obtained at the level of 1.6$10^{\text{-7}}$, which is limited by the friction of the rotating gyroscope. It means the spin-gravity interaction between the extended bodies has not been observed at this level.Comment: 4 page

Small Scale Structure Formation in Chameleon Cosmology

Chameleon fields are scalar fields whose mass depends on the ambient matter density. We investigate the effects of these fields on the growth of density perturbations on sub-galactic scales and the formation of the first dark matter halos. Density perturbations on comoving scales $R < 1 {\rm pc}$ go non--linear and collapse to form structure much earlier than in standard $\Lambda$CDM cosmology. The resulting mini-halos are hence more dense and resilient to disruption. We therefore expect (provided that the density perturbations on these scales have not been erased by damping processes) that the dark matter distribution on small scales would be more clumpy in chameleon cosmology than in the $\Lambda$CDM model.Comment: 13 pages, 4 figure

"Galileo Galilei" GG webpage: A small satellite to test the Equivalence Principle of Galileo, Newton and Einstein to 1 part in 10^17 (4 orders of magnitude improvement)

Webpage of the GG space project with direct access to all puplished papers, space mission studies, docuemntation and lab prototype experimental results. Accessible anytime from anywhere in the world. Initiated in 1998 and continuosly update

Equivalence Principle test in space

The discovery of “Dark Energy” and the fact that only 5% of the mass of the Universe is explained by current Physics laws have led to a serious impasse. A very high-accuracy space test of the Equivalence Principle with the GG (“Galileo Galilei”) mission would prove or rule out the existence of a new long-range interaction in Nature and be a crucial asset for the future of Physics and Cosmology