عنوان مقاله [English]
With the emergence of novel technologies and prevalence of social media, new horizons have been introduced into radio programs. In fact, radio is a platform that can have mutual interactions with the audience and gain their trust and loyalty. Hence, it is essential to analyze the factors affecting user participation and engagement in radio programs. This study aimed to identify and list the effective factors in improving user participation in the international English radio programs of IRIB World service on Instagram. For this purpose, the theories of media use, gratification, and convergence were applied. The thematic analysis was then adopted, and semi-structured interviews were conducted to collect data from 15 media experts. According to the research findings, effective factors of the audience engagement in IRIB World Service's social media (e.g., English radio programs on Instagram) had eight main themes. “Interaction with the audience”, “specialty, acquaintance, and in-time use of social media functions”, and “identification of the audience in radio newsrooms” are among the effective factors in the audience participation. The in-time use of “strategies for improving the audience engagement (participation)” and “involvement of the audience in media contents” can also affect the user behavior in participation. The research results indicated that themes of “media policy”, “ethical and cultural considerations”, and “policymaking documents and international strategies” directly affect participation and engagement of the audience and can contribute to IRIB World Service media to have active and loyal audience.