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We have analysed the light curve of the two brightest X-ray flares from theGalactic Center black hole, one flare observed by XMM-Newton on October 3, 2002(Porquet et al. 2003), and the other flare observed by Chandra on October 26,2000 (Baganoff et al. 2001). The power density spectra show five distinct peaksat periods of ~ 100 s, 219 s, 700 s, 1150 s, and 2250 s common to bothobservations within their estimated measurement uncertainties. The powerdensity spectrum of the recently reported infrared flare of June 16, 2003(Genzel et al. 2003) shows distinct peaks at two, if not three, periods(including the 1008 +/- 120 s infrared period), which are consistent with theX-ray periods. The remaining two periods could not be covered by the infraredmeasurements. Each period can be identified with one of the characteristicgravitational cyclic modes associated with accretion disks, i.e. eitherLense-Thirring precession, Kepler orbital motion and the vertical and radialepicyclic oscillation modes, in such a way that a consistent value for theblack hole mass of M_BH = 2.72^{+0.12}_{-0.19} x 10^6 M_odot and the angularmomentum $a$ = 0.9939^{+0.0026}_{-0.0074} is obtained. The available data onM_BH derived from studies of the orbital motion of the S2 (S0-2) star (Schoedelet al. 2002, Ghez et al. 2003) agree with our findings. Finally we discuss someimplications of the fairly high value for the angular momentum.Comment: In this revised version (accepted by the A&A Editor, 9 pages), we use  the formula for the Lense-Thirring precession given by Merloni et al. (1999),  which is not restricted to the weak-field limit. Thereby we now obtain a  unique solution for the mass and the angular momentum of the supermassive  black hol

X-ray flares reveal mass and angular momentum of the Galactic Center black hole