The Maruyama group is exploring several topics in nuclear and particle astrophysics ranging from studying properties of neutrinos to a search for dark matter. We are carrying out experiments to search for annual modulation signature from dark matter with the COSINE-100 and DM-Ice experiments. HAYSTAC is looking for the cosmic dark matter in the form of Axions. With CUORE, we are looking for a process called neutrinoless double beta decay. If such a process is observed, it would mean that neutrinos are their own antiparticles, and may hold the clue to why we live in a Universe of matter, and not antimatter. The experiment is located at the Gran Sasso National Underground Laboratory in Italy. We are using the IceCube Neutrino Observatory to study fundamental properties of neutrinos using nearby supernovae.
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HAYSTAC (Haloscope At Yale Sensitive To Axion CDM) is looking for dark matter in the form of Axions which are very low mass particles that are predicted in the context of the standard model of electroweak interactions (quark, gluon, W, Z, Higgs, etc. are all part of this model). If they do indeed exist and form dark matter, they will convert to radiofrequency photons in the presence of a strong magnetic field. The photon energy, hence frequency, is essentially determined by the axion mass, and is expected to be in the 1-20 GHz region. The heart of our experiment is a tunable radiofrequency (microwave) cavity resonator, which serves to build up the axion signal, and a quantum limited amplifier based on the Josephson effect which occurs when Cooper pairs tunnel though an insulating layer separating two superconductors. |
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COSINE-100 is a dark matter experiment currently running at the Yangyang Underground Laboratory (Y2L) in South Korea. Currently we are running 100 kg of NaI detectors at Y2L. These detectors have started taking data in Fall 2016, with an aim to test DAMA Collaboration’s claim that they have made a direct detection of dark matter with their thallium-doped sodium iodide detectors. |
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CUORE stands for “Cryogenic Underground Observabory for Rare Events”. Located at the Gran Sasso National Underground Laboratory in Italy, the main goal of the experiment is to look for a process called neutrinoless double beta decay. If such a process is observed, it would mean that neutrinos are their own antiparticles, and may hold the clue to why we live in a Universe of matter, and not antimatter. With CUORE, we can also look for dark matter and annual modulation signals. CUORE@Yale / Official CUORE Site |
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DM-Ice is searching for dark matter in the southern hemisphere. The goal is to perform a search for dark matter using the time variation resulting from the motion of the detector relative to the dark matter halo as a signature. The Antarctic ice offers a clean environment to conduct a dark matter experiment, complete with scientific infrastructure provided by the NSF South Pole Station. If confirmed, the observation would revolutionize our understanding of particle physics and cosmology. 17 kg of thallium-doped sodium iodide detectors have been running at the South Pole since 2011. |
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IceCube Neutrino Observatory: The IceCube Neutrino Detector is a neutrino telescope that finished construction in February 2011 at the South Pole. IceCube uses deep Antarctic ice instrumented with 5160 photomultiplier tubes (PMTs) at depths between 1,450 and 2,450 meters. The main goal of the experiment is to detect neutrinos in the high energy range, spanning from 1011 eV to about 1021 eV. Prof. Maruyama’s focus is in the low energies. IceCube can also detect 10 MeV neutrinos coming from nearby supernovae. We study how supernovae explode as well as fundamental properties of neutrinos (theta-13, mass hierarchy, etc.). With the addition of DeepCore, we can study ~100 GeV neutrinos to study atmospheric neutrino oscillation and dark matter collected in the Sun, Earth, and the Galactic Center. The addition of PINGU would bring the energy threashold down to 10 GeV. |