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We present the results of a comprehensive investigation on the evolution ofspectral and timing properties of the Galactic black hole candidate 4U 1630--47during its spectral transitions. In particular, we show how a scaling of thecorrelation of the photon index of the Comptonized spectral component Gammawith low frequency of quasi-periodic oscillations (QPO), nu_L and massaccretion rate, $\dot M$ can be applied to the black hole mass and theinclination angle estimates. We analyze the transition episodes observed withthe {\it Rossi} X-ray Timing Explorer (RXTE) and BeppoSAX satellites. We findthat the broadband X-ray energy spectra of 4U~1630--47 during all spectralstates can be modeled by a combination of a thermal component, a Comptonizedcomponent and a red-skewed iron line component. We also establish that Gammamonotonically increases during transition from the low-hard state to thehigh-soft state and then saturates for high mass accretion rates. The indexsaturation levels vary for different transition episodes. Correlations of Gammaversus nu_L also shows saturation at Gamma ~ 3. Gamma-Mdot and Gamma-nu_Lcorrelations with their index saturation revealed in 4U~1630--47 are similar tothose established in a number of other BHCs and can be considered as anobservational evidence for the presence of a black hole in these sources. Thescaling technique, which relies on XTE J1550--564, GRO 1655-40 and H 1743-322as reference sources, allows us to evaluate a black hole mass in 4U~1630--47yielding M_{BH}~10+/- 0.1 solar masses, and to constrain the inclination angleof i< 70 degrees.

Black hole mass determination in the X-ray binary 4U 1630--47: Scaling of spectral and variability characteristics