Writing a std::vector<unsigned long> in a Branch

Hi all,
I’m triyng to create an array of stl vectors:

std::vector<word> _AMDigi[maxNTrk]; 

and save it in a Branch:


The code compiles but then it crashes when trying to fill:

I have defined:

typedef unsigned long int word;
/* ... */
#pragma link C++ class std::vector<word>;

I have searched in the forum but didn’t find anything similar.
Root version in 5.18

Many thanks in advance,

This should be OK in ROOT5.20, but not in 5.18.
in 5.18 you must create a td::vector *_AMDigi[maxNTrk]; using new