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We present an investigation of line-of-sight (LOS) velocity oscillations insolar faculae and sunspots. To study the phase relations between chromosphereand photosphere oscillations of the LOS velocity, we measured the time lag ofthe chromospheric signal relative to the photospheric one for several faculaeand sunspots in a set of spectral line pairs. The measured time lags aredifferent for different objects. The mean measured delay between theoscillations in the five-minute band in faculae is 50s for the SiI10827{\AA}-HeI 10830{\AA} pair; for the pair FeI 6569{\AA}-H-alpha 6563{\AA}the mean delay is 20s; for the pair FeI 4551{\AA}-BaII 4554{\AA} the mean delayis 7s; for the pair SiI 8536{\AA}-CaII 8542{\AA} the mean delay is 20s. For theoscillations in the three-minute band in sunspot umbrae the mean delay is 55sfor the SiI 10827{\AA}-HeI 10830{\AA} pair; for the Fe I 6569{\AA}-H-alpha6563{\AA} pair it was not possible to determine the delay; for the FeI4551{\AA}-BaII 4554{\AA} pair the mean delay is 6s; for the SiI 8536{\AA}-CaII8542{\AA} pair the mean delay is 21s. Measured delays correspond to the wavepropagation speed which significantly exceeds the generally adopted speed ofsound in the photosphere. This raises the question of the origin of theseoscillations. The possibility that we deal with slow MHD waves is not ruledout.

Direct measurement results of the time lag of LOS-velocity oscillations between two heights in solar faculae and sunspots