SIMBAD references

We study the effects on the number counts of submillimetre galaxies due to gravitational lensing. We explore the effects on the magnification cross-section due to halo density profiles, ellipticity and cosmological parameter (the power-spectrum normalization σ8). We show that the ellipticity does not strongly affect the magnification cross-section in gravitational lensing while the halo radial profiles do. Since the baryonic cooling effect is stronger in galaxies than clusters, galactic haloes are more concentrated. In light of this, a new scenario of two-halo-population model is explored where galaxies are modelled as a singular isothermal sphere profile and clusters as a Navarro, Frenk and White profile. We find that the transition mass between the two has modest effects on the lensing probability. The cosmological parameter σ8 alters the abundance of haloes and therefore affects our results. Compared with other methods, our model is simpler and more realistic. The conclusions of previous works confirm that gravitational lensing is a natural explanation for the number count excess at the bright end.