The period distribution of the new X-ray pulsators above about 2,000s resembles that of cataclysmic variables, while there is a paucity of sources with shorter period and low fluxes. More than 50 per cent of the signals were confirmed by further Chandra (for those sources with two or more pointings), XMM-Newton or ROSAT data. With these numbers, the ChAndra Timing Survey at Brera And Roma astronomical observatories - as we called the project - represents the largest ever systematic search for coherent signals in the classic X-ray band. We carried out the search for new X-ray pulsators in light curves with more than 50 photons, for a total of about 190,000 lightcurves out of about 430,000 extracted. The archival data of the first 15 years of Chandra observations were retrieved and analysed by means of fast Fourier transforms, employing a peak-detection algorithm able to screen candidate signals in an automatic fashion. We report on the discovery of 41 new pulsating sources in the data of the Chandra Advanced CCD Imaging Spectrometer, which is sensitive to X-ray photons in the 0.3-10 keV band. Accepted for publication in Astrophysical Journal, September 10 edition We discuss several possible reasons for this observed excess.

This number is in excess of predictions made with a simple CV model based on a local CV space density of <~ 10^-5 pc^-3, and a scale height ~200pc. We report the discovery of three new X-ray detected cataclysmic variables (CVs) in the direction of the Galactic Center (at distances ~2kpc). We identify one candidate quiescent low-mass X-ray binary with a sub-giant companion we note that this object may also be an RS CVn system. We present the discovery of a population of stellar coronal emission sources, likely consisting of pre-main sequence, young main sequence and main sequence stars, as well as a component of active binaries of RS CVn or BY Dra type. We use a combination of optical spectral fitting and quantile X-ray analysis to obtain the hydrogen column density towards each object, and a three-dimensional dust model of the Galaxy to estimate the most probable distance in each case. We have carried out optical and X-ray spectral analyses on a sample of 136 candidate optical counterparts of X-ray sources found in five Galactic-bulge fields included in our Chandra Multi-wavelength Plane Survey.

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