In 2019A semester, 10 radio telescopes (KVN 3 × 21 m, VERA 4 × 20 m, Nobeyama 45 m, Tianma 65 m, and Nanshan 26 m) are available for EAVN open use, as shown in Figure 1. Refer to the KaVA Status Report for more details about KaVA’s array performance. Two observing frequencies, 22 (K-band) and 43 GHz (Q-band), are opened in 2019A semester. The maximum angular resolution is 0.55 mas at K-band for VERA-Ogasawara – Nanshan baseline and 0.63 mas at Q-band for VERA-Mizusawa – VERA-Ishigakijima baseline). The geographic locations and coordinates of Nobeyama, Tianma, and Nanshan, as well as KaVA, are summarized in Table 1. Figure 2 shows examples of (u, v) coverage.
|Examples of (u, v) coverage for an EAVN observation with full array conﬁguration at 22 GHz (upper panels) and 43 GHz (lower panels) with the source’s declination of +60◦ (left panels), +20◦ (middle panels), and −20◦ (right panels). Total observation duration of 10 hours and the antenna elevation limit of 15◦ are assumed for all cases.|