Benchmark calculation of total cross sections for ionization-excitation of helium

The total cross section for simultaneous ionization-excitation of helium by electron impact has been revisited within the framework of the fully non\-perturbative $B$-spline $R$-matrix with pseudo\-states (BSRMPS) approach~[1]. This is a highly challenging 4-body Coulomb problem that cannot be simplified by effectively treating one of the target electrons as a spectator. After successfully applying the BSRMPS method to the energy- and angle-differential problem~[2], we investigated a long-standing discrepancy regarding the absolute normalization of the cross section for ionization with simultaneous excitation of the residual ion into the He$^+$(2p) state. Our calculations strongly favor the values suggested in [3,4] rather than the re\-normalization proposed in~[5].\\[4pt] [1]~O.~Zatsarinny and K.~Bartschat, J.~Phys.~B~{\bf 46} (2013) 112001.\\[0pt] [2]~O.~Zatsarinny and K.~Bartschat, Phys.~Rev.~Lett.~{\bf 107} (2011) 023203.\\[0pt] [3]~E.W.O.~Bloemen, H.~Winter, T.D.~M\"ark, D.~Dijkkamp, D.~Barends, and F.J.~de~Heer, J.~Phys.~B {\bf~14} (1981) 717.\\[0pt] [4]~J.J.~Forand, K.~Becker, and J.W.~McConkey, J.~Phys.~B {\bf~18} (1985) 1409.\\[0pt] [5]~H.~Merabet, R.~Bruch, S.~F\"ulling, K.~Bartschat, and A.L.~Godunov, J.~Phys.~B~{\bf~36} (2003) 3383.