arXiv:1102.1869v1 [hep-ph] 9 Feb 2011 Absolute values of nonstandard interaction parameters in ν e e and ¯ ν e e−scatterings. Amir Nawaz Khan * , Farida Tahir † Department of Physics, COMSATS Institute of InformationTechnology, Park Road, Islamabad, Pakistan. April 17, 2019 Abstract We present a novel approach for constraining nonstandard neutrino interaction (NSI) coupling parameters (ε eL ee and ε eR ee ) in low energy flavor conserving νee and ¯ νee-scattering processes. Here we exploit an im- portant phenomenon of interference and assuming that ε eL ee and ε eR ee are same for both the processes as gL and gR in the standard model (SM). Using this approach we obtain the absolute values ε eL ee =8.7 × 10 -3 and ε eR ee =3.8 × 10 -1 , while the bounds obtained using the said pro- cesses are -0.11 <ε eL ee < 0.13 and 0.35 <ε eR ee < 0.41. It is noteworthy that the lower bound on ε eR ee exclude the negative region. Furthermore, our bounds on ε eR ee are more stringent than the existing ones. Key words: Neutrino mass, Nonstandard neutrino interactions, In- terference effect, New physics. 1 Introduction The discovery of neutrino masses in the neutrinos oscillation experiments ne- cessitates the existance of new interactions called nonstandard neutrino interac- tions (NSI) [1, 2, 3, 4]. These new interactions along with the massive neutrinos are predicted by various models [5, 6], involving those where neutrinos aquire masses through see-saw mechanism [7, 8, 9, 10, 11], those where neutrinos gain masses radiatively due to the presence of extra Higgs bosons [12, 13, 14] and the R-parity violating supersymmetic models [15, 16, 17, 18, 19]. At low energy effective level the currrent structure of the NSI is similar to that of four Fermi interactions [20]. The NSI may be nonuniversal flavor- conserving or flavor- changing contrary to standard model (SM) currents which are universal and flavor conserving. * amir nawaz@comsats.edu.pk † farida tahir@comsats.edu.pk 1