Key technologies and cutting-edge sciences in advanced submillimeter telescopes

<p indent="0mm">The submillimeter band plays a pivotal role in astronomy as an essential observational window, facilitating access to unique cosmic phenomena that are fundamental to our understanding of the universe. It enables the exploration of profound scientific inquiries of our time, encompassing the study of cosmic reionization, surveys of high-redshift galaxies, investigations into the origin of life, and black hole research. This field is currently experiencing rapid development driven by prominent international projects such as the Atacama Large Millimeter/submillimeter Array (ALMA), which stands as a global leader in high-resolution submillimeter observations. Collaborations like the Event Horizon Telescope (EHT) and the forthcoming next generation Event Horizon Telescope (ngEHT) further contribute to these advancements. These remarkable progressions underscore the vital role played by international cooperation in submillimeter astronomy and have motivated Chinese scientists to assess their competitive landscape, evaluate scientific requirements, and strategize for China’s advancement in this domain. China’s core research teams in submillimeter astronomy not only evaluate immediate and long-term research needs but also develop strategies ensuring active participation within this field. This strategy involves leveraging China’s geographical advantages, technological capabilities, and growing pool of scientific talent. Emphasis is placed on developing advanced observational facilities and instruments that meet international standards with particular focus on unique observation sites located on China’s Tibetan plateau and Antarctica regions. These regions offer rare pristine observation conditions that could prove crucial for China’s emerging submillimeter projects while complementing existing international facilities. Internationally, countries with advanced submillimeter facilities, such as those in the U.S. and Europe, have made groundbreaking discoveries. For instance, ALMA has played a crucial role in observing high-redshift galaxies, early stages of star formation, and even imaging black hole event horizons. These achievements have prompted Europe and the United States to develop plans for the next generation of submillimeter telescopes, including projects like the Large Submillimeter Telescope (LST) and the Atacama Large Aperture Submillimeter Telescope (AtLAST). These upcoming facilities aim to overcome the limitations of current equipment by offering enhanced sensitivity, wider fields of view, and faster survey capabilities. China’s infrastructure for submillimeter astronomy currently lags behind its optical and radio astronomy fields where world-leading projects like the Five-hundred-meter Aperture Spherical radio Telescope (FAST) have propelled Chinese research to international prominence. China’s existing radio astronomy infrastructure primarily focuses on lower-frequency observations within meter and centimeter wavelength ranges. The highest-frequency capability is represented by China’s 13.7-meter millimeter-wave telescope in Delingha operating within the <sc>3 mm</sc> band. However, China has taken steps towards addressing this gap in submillimeter technology by relocating the LCT (Leton Chajnantor Telescope) submillimeter telescope from Hawaii to a site in Chile—An encouraging advancement towards building submillimeter capability. As China’s research teams look ahead to the science and technology goals outlined for 2035, submillimeter astronomy has been identified as a pivotal area of focus. The emphasis lies on cutting-edge research that capitalizes on unique domestic resources and advances detector technologies to facilitate observations in the submillimeter range. National endeavors in submillimeter astronomy aim to support crucial scientific objectives and achieve transformative technological breakthroughs. These advancements will not only enhance China’s competitiveness in the international astronomy field but also drive progress across various domains, including telecommunications, atmospheric science, biomedical science, and national security.