Opt and NIR phot. follow-up of iPTF SNIa

This new data set covers a broad range of redshifts and host galaxy stellar masses, compared to previous SN Ia efforts in the NIR. We construct a sample, using also literature data at optical and NIR wavelengths, to examine claimed correlations between the host stellar masses and the Hubble diagram residuals.

The SN magnitudes are corrected for host galaxy extinction using either a global total-to-selective extinction ratio, RV=2.0, for all SNe, or a best-fit RV for each SN individually. Unlike previous studies that were based on a narrower range in host stellar mass, we do not find evidence for a "mass step," between the color- and stretch- corrected peak J and H magnitudes for galaxies below and above log(M_*_/M_{sun}_)=10.