The signal cross sections for the process [e.sup.-]p [right arrow] ([e.sup.-]t + [e.sup.-][bar.t]) + X for different values of couplings [[lambda].sub.u] and [[lambda].sub.c] at the LHeC are given in Table 1.
In this section, we study the sensitivity to anomalous top FCNC couplings through the signal and background process [e.sup.-]p [right arrow] [e.sup.-][W.sup.[+ or -]]q+X at LHeC. This process includes the off-shell single top quark production and interfering background with the signal.
Since the LHeC has an energy asymmetry, the jets from the process mainly peaked in the backward region according to the ep collisions; therefore the pseudo-rapidity range for jets is taken to be -4 < [eta](j) < 0 for the analysis.
Here [L.sub.int] is the integrated luminosity of the ep collider and we choose [L.sub.int] = 100 [fb.sup.-1] as the LHeC design luminosity.
We searched for the excited spin-3/2 neutrino signal at lepton-hadron collider LHeC for two different centers of mass energies.
It is possible to search for single production of excited spin-3/2 neutrinos at the LHC but it has smaller cross-section than LHeC. Therefore, the potential of LHeC is better than LHC to determine the limits on couplings of excited spin-3/2 neutrinos.
Concerning ILC[cross product]SppC based ep colliders, a new scheme for energy recovery proposed for higher-energy LHeC (see Section 7.1.5 in ) may give an opportunity to increase luminosity by an additional order, resulting in [L.sub.ep] exceeding [10.sup.33] [cm.sup.-2] [s.sup.-1].
For LHeC with [square root of s] = 1.3 TeV minimal achievable value is x = 6 x [10.sup.-6].
Turkoz, "Resonant production of color octet electron at the LHeC," Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics, vol.
In Figure 4 (cut-based analysis) and Figure 5 (MVA-based analysis) , we plot the contours of 1a limits to [[kappa].sub.tqH] at 7 (50) GeV LHeC and 60 (120) GeV electron beam with different polarization.
A detailed comparison between the LHeC collider(s) and the LHC or linear colliders is given.
In this paper, we investigated the anomalous FCNC Yukawa interactions between the top quark, the Higgs boson, and either an up or charm quark with a channel [e.sup.-]p [right arrow] [v.sub.e][bar.t] [right arrow] [v.sub.e]h[bar.q](h [right arrow] b[bar.b]) at the LHeC. The signal significance S/[square root of S + B] can be obtained as 4.191 (4.921), 6.652 (7.874), 15.341 (16.934), and 19.238 (20.785) with the cut-based (MVA-based) method at ([E.sub.p], [E.sub.e]) = (7 TeV, 60 GeV), ([E.sub.p], [E.sub.e]) = (7 TeV, 120 GeV), ([E.sub.p], [E.sub.e]) = (50 TeV, 60 GeV), and ([E.sub.p], [E.sub.e]) = (50 TeV, 120 GeV).