  Motivated by the recent experimental results of branching fractions for
D_((s))^+ arrows {\eta}^((')) l^+ {\nu}_l decays, which deviate from their SM
predictions, we have investigated these decays in W' model and scalar
leptoquark model to find possible signatures of new physics (NP) in
semileptonic charm decays induced by c arrow(s,d)l {nu}_l transitions. Using
recent experimental results of branching fractions for semileptonic D meson
decays, new coupling parameters are predicted for the above NP models.
Branching fraction, forward-backward asymmetry and lepton polarization
asymmetry are studied taking the predicted NP coupling parameters. Results of
branching fractions in scalar leptoquark model are found very close to the
experimental results and exist around the range 1{sigma} deviation. We have
presented a comparative study of the NP models to check their sensitivity on
these decays. We anticipate that further research on these decays will
significantly support our findings.
