/usr/include/ThePEG/Helicity/Vertex/Scalar/ is in libthepeg-dev 1.8.0-1.
This file is owned by root:root, with mode 0o755.
..
/usr/include/ThePEG/Helicity/Vertex/Scalar/FFSVertex.fh
/usr/include/ThePEG/Helicity/Vertex/Scalar/FFSVertex.h
/usr/include/ThePEG/Helicity/Vertex/Scalar/GeneralVVSVertex.fh
/usr/include/ThePEG/Helicity/Vertex/Scalar/GeneralVVSVertex.h
/usr/include/ThePEG/Helicity/Vertex/Scalar/RFSVertex.fh
/usr/include/ThePEG/Helicity/Vertex/Scalar/RFSVertex.h
/usr/include/ThePEG/Helicity/Vertex/Scalar/SSSSVertex.fh
/usr/include/ThePEG/Helicity/Vertex/Scalar/SSSSVertex.h
/usr/include/ThePEG/Helicity/Vertex/Scalar/SSSVertex.fh
/usr/include/ThePEG/Helicity/Vertex/Scalar/SSSVertex.h
/usr/include/ThePEG/Helicity/Vertex/Scalar/VSSVertex.fh
/usr/include/ThePEG/Helicity/Vertex/Scalar/VSSVertex.h
/usr/include/ThePEG/Helicity/Vertex/Scalar/VVSSVertex.fh
/usr/include/ThePEG/Helicity/Vertex/Scalar/VVSSVertex.h
/usr/include/ThePEG/Helicity/Vertex/Scalar/VVSVertex.fh
/usr/include/ThePEG/Helicity/Vertex/Scalar/VVSVertex.h