The supernova SN 2001du was discovered in the galaxy NGC1365 at a distance of 19 \pm 2 Mpc , and is a core-collapse event of type II-P .
Images of this galaxy , of moderate depth , have been taken with the Hubble Space Telescope approximately 6.6 years before discovery and include the supernova position on the WFPC2 field of view .
We have observed the supernova with the WFPC2 to allow accurate differential astrometry of SN 2001du on the pre-explosion frames .
As a core-collapse event it is expected that the progenitor was a massive , luminous star .
There is a marginal detection ( 3 \sigma ) of a source close to the supernova position on the prediscovery V - band frame , however it is not precisely coincident and we do not believe it to be a robust detection of a point source .
We conclude that there is no stellar progenitor at the supernova position and derive sensitivity limits of the prediscovery images which provide an upper mass limit for the progenitor star .
We estimate that the progenitor had a mass of less than 15M _ { \odot } .
We revisit two other nearby SNe II-P which have high quality pre-explosion images , and refine the upper mass limits for the progenitor stars .
Using a new distance determination for SN 1999gi from the expanding photosphere method , we revise the upper mass limit to 12M _ { \odot } .
We present new HST images of the site of SN 1999em , which validate the use of lower spatial resolution ground-based images in the progenitor studies and use a new Cepheid distance to the galaxy to measure an upper mass limit of 15M _ { \odot } for that progenitor .
Finally we compile all the direct information available for the progenitors of eight nearby core-collapse supernovae and compare their mass estimates .
These are compared with the latest stellar evolutionary models of pre-supernova evolution which have attempted to relate metallicity and mass to the supernovae type .
Although this is statistically limited at present , reasonable agreement is already found for the lower mass events ( generally the II-P ) , but some discrepancies appear at higher masses .