A terminal apparatus and a base station apparatus can efficiently communicate with each other through downlink. A terminal apparatus detects a first physical layer cell identity (PCI) through cell search and receives system information, a first RS, and a second RS. The system information is used to indicate at least (i) a second PCI, (ii) a transmission bandwidth of EUTRA and an offset associated with a physical resource block index, and (iii) an operation of NB-IoT. A first sequence of the first RS is identified based at least on the first PCI. A second sequence of the second RS is identified based at least on the second PCI and the offset.