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We investigate the early phase of the first state change during the 2008September-November outburst of H1743-322, first detected by the INTEGRALsatellite. We analyse INTEGRAL, RXTE, Swift, and XMM/Newton observations, whichprovide coverage of the quiescence to outburst evolution in the 3-200 keV rangeevery few days. The energy spectra are well fitted by a phenomenological modelconsisting of an exponentially cut-off power law plus a disc component. A morephysical model of thermal Comptonisation (and a disc) represents the spectraequally well. In a first phase (up to MJD 54760), the photon index andtemperature of the disc do not vary significantly, and have values reminiscentof the Hard State (HS). The timing analysis is also consistent with that of aHS, and shows in particular a rather high degree of variability (~30%), and astrong ~0.5-1 Hz QPO with its first harmonic. The timing and spectralcharacteristics of H1743-322 are similar to those of the first HS during its2003 outburst. After MJD 54760, a change to softer spectra and a ~5-6 Hz QPOindicate that the source underwent a state transition into a Hard-IntermediateState (HIMS). We observe in both states a correlation between the QPO frequencyand the photon index, which indicates a strong link between the accretion disc,generally understood to determine the QPO frequency, and the corona, whichdetermines the QPO power. The gradual disappearance of the QPO harmonic, andthe slowly decreasing hard X-ray flux, imply that the accretion disc graduallymoved inwards during the HS.

The early phase of a H1743-322 outburst observed by INTEGRAL, RXTE, Swift, and XMM/Newton