  SNe II show growing evidence of interaction with CSM surrounding their
progenitor stars as a consequence of enhanced mass loss during the last years
of the progenitor's life. We present an analysis of the progenitor mass-loss
history of SN2023ixf, a nearby SN II showing signs of interaction. We calculate
the early-time bolometric light curve (LC) for SN2023ixf based on the
integration of the observed flux covering UV, optical and NIR bands, and
black-body extrapolations for the unobserved flux. Our calculations spot the
sudden increase to maximum luminosity and temperature, in addition to the
subsequent fall, displaying an evident peak. This is the first time that this
phase can be precisely estimated for a SN II showing interesting
characteristics as: 1) slope changes during the rise to maximum luminosity; and
2) a very sharp peak with a maximum luminosity of $\sim$3$\times$10$^{45}$erg
s$^{-1}$. We use the bolometric LC of SN2023ixf to test the calibrations of
bolometric corrections against colours from the literature. In addition, we
include SN2023ixf into some of the available calibrations to extend their use
to earlier epochs. Comparison of the observed bolometric LC to SN II explosion
models with CSM interaction suggests a progenitor mass-loss rate of
3$\times$10$^{-3}M_{\odot}$yr$^{-1}$ confined to 12000$R_{\odot}$ and a wind
acceleration parameter of $\beta$=5. This model reproduces the early bolometric
LC, expansion velocities, and the epoch of disappearance of interacting lines
in the spectra. This model indicates that the wind was launched $\sim$80yr
before the explosion. If the effect of the wind acceleration is not taken into
account, the enhanced wind must have developed over the final months to years
prior to the SN, which may not be consistent with the lack of outburst
detection in pre-explosion images over the last $\sim$20yr before explosion.
