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Using three fiducial Nbody+SPH simulations, we follow the merging of two diskgalaxies with a hot gaseous halo component each, and examine whether the mergerremnant can be a spiral galaxy. The stellar progenitor disks are destroyed byviolent relaxation during the merging and most of their stars form a classicalbulge, while the remaining form a thick disk and its bar. A new stellar diskforms subsequently and gradually in the remnant from the gas accreted mainlyfrom the halo. It is vertically thin and well extended in its equatorial plane.A bar starts forming before the disk is fully in place, contrary to what isassumed in idealised simulations of isolated bar-forming galaxies. It hasmorphological features such as ansae and boxy/peanut bulges. Stars of differentages populate different parts of the box/peanut. A disky pseudobulge formsalso, so that by the end of the simulation, all three types of bulges coexist.The oldest stars are found in the classical bulge, followed by those of thethick disk, then by those in the thin disk. The youngest stars are in thespiral arms and the disky pseudobulge. The disk surface density profiles are oftype II (exponential with downbending), and the circular velocity curves areflat and show that the disks are submaximum in these examples: two clearly soand one near-borderline between maximum and submaximum. On average, onlyroughly between 10 and 20% of the stellar mass is in the classical bulge of thefinal models, i.e. much less than in previous simulations.

Forming disk galaxies in wet major mergers. I. Three fiducial examples