I don't know what you're really trying to do, but I foresee two possible scenarios:

Pass a reference to a new array containing copies of the scalars in the slice. It's simple and clear:

$ perl
my @a = qw/a b c d e/;

sub printthese {
  local $, = ', ';
  print @{$_[0]};
  print "\n";
}

printthese( [ @a[0, 2, 4] ]);
^D
a, c, e
[download]

Pass a reference to a new array containing aliases to the scalars in the slice, so you can modify them

$ perl
my @a = qw/1 2 3 4 5/;

sub zerothese {
  $_ = 0 for @{$_[0]};
}

zerothese( &{sub {\@_}} (@a[0, 2, 4]) );

print join ', ', @a;
print "\n";
^D
0, 2, 0, 4, 0
[download]