For most graduate students, research trips primarily mean conferences. For Aishwarya Vijai, it meant a month at Summit Station, Greenland, deep inside the Arctic Circle. Summit Station is located near the apex of the Greenland ice sheet at an elevation of ~10,000 feet above sea level. The station hosts scientists from collaborations around the world to conduct experiments on and with the Greenland ice sheet. One such collaboration is the Radio Neutrino Observatory in Greenland (RNO-G), a next-generation, ultra-high energy (UHE) neutrino detector. RNO-G sends teams of 4-5 people to help build the detector, and this year, these teams included a student from UMD: Aishwarya, a fourth-year graduate student in the physics department. Aishwarya works with Assistant Professor Brian Clark. The team flew to Summit Station via miltary aircrafts called LC-130s from Kangerlussuaq, a small town in Western Greenland. They stayed at Summit Station for a month to do maintenance work and collect data for calibration purposes.
From Summit Station, the RNO-G detector, which is spread out over multiple locations (“stations”) on the ice sheet, is accessed via snow machines. Primary work done by this year included raising structures like solar panels and wind turbines which are used to power the detector. This involved a lot of shoveling to remove the drifting snow and attaching extensions to the bases of these structures to raise their heights. In addition, the team collected critical data to better understand the detector’s performance. This was achieved by campaigns where antennas were lowered hundreds of feet into the ice sheet.
Summit Station has a maximum capacity of 40 people and operates 6 days a week with Sundays off. The biggest building on station is the aptly named Big House, a common area for meals, bathrooms, showers and entertainment in the form of books and board games. Food is prepared on station by a chef 6 days a week with leftovers on Sundays. Additional amenities include a gym, a recreational tent with a projector for watching movies, and a sauna. Sleeping accommodations are in the form of fish huts (small hard-sided structures for 1 person), the Flarm and the Caboose (hard-sided structures for 6-8 people).
Temperatures at Summit Station typically fluctuate around -10 degrees Fahrenheit with wind chill, with occasional storms generating wind gusts of up to 50 mph. All people on Summit Station are equipped with winter gear to handle extreme weather. The station is located within the Arctic Circle so the sun doesn’t set in the summer until the beginning of August. The constant sunlight reflecting off the ice sheet leads to a high albedo. Sunglasses are worn outside at almost all times.
Summit Station and the surrounding ice sheet was an incredible place to visit. The ice sheet is extremely beautiful and vast, appearing almost infinite in size. There are also several cool phenomena that can be observed on the ice sheet, like sun dogs and halos, which are produced when sunlight refracts through the ice crystals in the atmosphere. Sunsets at Summit Station saturate the sky in shades of red and yellow that appear even brighter in contrast to the white surroundings. The community at Summit Station also made the experience incredible, turning a nearly inhospitable place into the place to be for an experience of a lifetime.
The Greenland ice sheet is one of the only places in the world where a UHE neutrino observatory like RNO-G can be built. The collaboration as a whole looks forward to returning next year and continuing work building the detector and hopefully using it to elevate our understanding of the universe at the highest of energies.
More About RNO-G
The Radio Neutrino Observatory in Greenland (RNO-G) is a UHE neutrino telescope located at Summit Station, Greenland. The detector aims to find UHE neutrinos potentially emitted from energetic phenomena in the universe like black hole mergers and supernovas (explosions of stars). The detector is currently under construction and the University of Maryland (UMD) is a major construction site. Currently, the RNO-G group at UMD has built nearly 250 antennas. These antennas are the primary detection unit of RNO-G and aim to find the broadband radio pulse that is produced when UHE neutrinos interact with ice.
The fully completed detector will have 35 stations spaced 1 km apart to create an array. Each station will be equipped with 24 antennas buried in the Greenland Ice Sheet in drilled holes ~100 meters in depth. 8 stations have been built so far.
