$('.cart_auth_btn').on('click', function() {
        var email = $("form[name='USER_LOGIN']").val();
        var pass = $("form[name='USER_PASSWORD']").val();
        $.ajax({
            type: "POST",
            url: "/ajax/try_auth.php",
            data: "email="+email+"&pass="+pass,
            success: function(eps) {
                console.log(eps);
                var perem = eps;
        }
        });
        if(perem.length > 1){
            console.log('Неверный логин');
        }
        return false;
    });