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sity near the Fermi level in the shape of the bulk hole pocket seen with hν = 24 eV photons, which is symmet- ric about ¯ Γ. This envelope does not change shape with hν suggesting that it is of surface origin. Due to its weak intensity relative to states at higher binding energy, these features cannot be easily seen in the energy distribution 

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curves (EDCs) in Fig. 2(a)-(c), but can be clearly ob- served in the MDCs shown in Fig. 1(c) especially on the positive k$_{x}$ side. Centered about the ¯ M point, we also observe a crescent shaped envelope of weak intensity that does not disperse with k$_{z}$ [Fig. 2(d)-(f)], point- ing to its surface origin. Unlike the sharp surface states near ¯ Γ, the peaks in the EDCs of the feature near ¯ M are much broader (Δ E ∼ 80 meV) than the spectrometer resolution (15 meV). The origin of this diffuse ARPES signal is not due to surface structural disorder because if that were the case, electrons at ¯ Γ should be even more severely scattered from defects than those at ¯ M. In fact, the occurrence of both sharp and diffuse surface states originates from a k dependent coupling to the bulk as discussed later. 

To extract the spin polarization vector of each of the surface bands near ¯ Γ, we performed spin resolved MDC measurements along the ¯ M’- ¯ Γ- ¯ M cut at E$_{B}$ = -30 meV for maximal intensity, and used the two-step fit- ting routine developed in [24]. The Mott detector in the COPHEE instrument is mounted so that at nor- mal emission it is sensitive to a purely out-of-plane spin component ( z $^{′}$) and a purely in-plane ( y $^{′}$) spin compo- nent that is rotated by 45 ◦ from the sample ¯ Γ- ¯ M di- rection [Fig. 3(a)]. Each of these two directions rep- 

