On March 25th 2019, the Belle II detector recorded the first collisions
delivered by the SuperKEKB accelerator. This marked the beginning of the
physics run with vertex detector.
The vertex detector was aligned initially with cosmic ray tracks without
magnetic field simultaneously with the drift chamber. The alignment
method is based on Millepede II and the General Broken Lines track model
and includes also the muon system alignment and part of drift chamber
calibrations. To control weak modes, we employ sensitive validation tools and
various track samples can be used as alignment input, from straight cosmic tracks to mass-constrained decays.
With increasing luminosity and experience, the alignment is approaching
the target performance, crucial for the first physics analyses in the
era of Super-B-Factories. We will present the software framework for the
detector calibration and alignment, the results from the first
physics run and the prospects in view of the experience with the first data.
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