About

Professor Reina Maruyama is an Associate Professor of Physics and Astronomy at Yale University, based in the Wright Laboratory. Her research group develops technologies and conducts experiments to probe the fundamental nature of the universe. The group investigates the underlying physics of fundamental symmetries, the origins of the universe, and the nature of neutrinos and dark matter. They utilize techniques from quantum sensor development, atomic physics, astrophysics, particle physics, and nuclear physics to address some of the greatest mysteries of cosmic evolution, including the composition of the universe and the matter-antimatter asymmetry. Professor Maruyama leads her lab in exploring these profound questions, contributing to our understanding of the universe's fundamental properties.

Research topics

• Particle physics
• Astronomy
• Physics
• Computer Science
• Astrophysics
• Nuclear physics
• Optics
• Remote sensing
• Telecommunications
• Electronic engineering

Selected publications

• Searching for VHE gamma-ray emission associated with IceCube neutrino alerts using FACT, H.E.S.S., MAGIC, and VERITAS

  Proceedings of 36th International Cosmic Ray Conference — PoS(ICRC2019) · 2021 · 10 citations

  • Physics
  • Astrophysics
  • Astronomy

  The realtime follow-up of neutrino events is a promising approach to search for astrophysical neutrino sources. It has so far provided compelling evidence for a neutrino point source: the flaring gamma-ray blazar TXS 0506+056 was observed in coincidence with the high-energy neutrino IceCube-170922A detected by IceCube. The detection of very-high-energy gamma rays (VHE, E > 100 GeV) from this source helped establish the coincidence and constrained the modeling of the blazar emission at the time of the IceCube event. The four major imaging atmospheric Cherenkov telescope arrays (IACTs) - FACT, H.E.S.S., MAGIC, and VERITAS - operate an active follow-up program of target-of-opportunity observations of neutrino alerts sent by IceCube. This program has two main components. One are the observations of known gamma-ray sources around which a cluster of candidate neutrino events has been identified by IceCube (Gamma-ray Follow-Up, GFU). The second one is the follow-up of single high-energy neutrino candidate events of potential astrophysical origin such as IceCube-170922A. GFU has been recently upgraded by IceCube in collaboration with the IACT groups. We present here recent results from the IACT follow-up programs of IceCube neutrino alerts and a description of the upgraded IceCube GFU system.

  DOI

• IceCube high-energy starting event sample: Description and flux characterization with 7.5 years of data

  Physical review. D/Physical review. D. · 2021 · 368 citations

  • Physics
  • Astrophysics
  • Astronomy

  The IceCube Neutrino Observatory has established the existence of a high-energy all-sky neutrino flux of astrophysical origin. This discovery was made using events interacting within a fiducial region of the detector surrounded by an active veto and with reconstructed energy above 60 TeV, commonly known as the high-energy starting event sample (HESE). We revisit the analysis of the HESE sample with an additional 4.5 years of data, newer glacial ice models, and improved systematics treatment. This paper describes the sample in detail, reports on the latest astrophysical neutrino flux measurements, and presents a source search for astrophysical neutrinos. We give the compatibility of these observations with specific isotropic flux models proposed in the literature as well as generic power-law-like scenarios. Assuming ${\ensuremath{\nu}}_{e}:{\ensuremath{\nu}}_{\ensuremath{\mu}}:{\ensuremath{\nu}}_{\ensuremath{\tau}}=1:1:1$, and an equal flux of neutrinos and antineutrinos, we find that the astrophysical neutrino spectrum is compatible with an unbroken power law, with a preferred spectral index of ${2.87}_{\ensuremath{-}0.19}^{+0.20}$ for the 68% confidence interval.

  DOI

• Sensitivity studies for the IceCube-Gen2 radio array

  Proceedings of 36th International Cosmic Ray Conference — PoS(ICRC2019) · 2021 · 49 citations

  • Computer Science
  • Physics
  • Astronomy

  The IceCube Neutrino Observatory at the South Pole has measured the diffuse astrophysical neutrino flux up to $\sim$PeV energies and is starting to identify first point source candidates. The next generation facility, IceCube-Gen2, aims at extending the accessible energy range to EeV in order to measure the continuation of the astrophysical spectrum, to identify neutrino sources, and to search for a cosmogenic neutrino flux. As part of IceCube-Gen2, a radio array is foreseen that is sensitive to detect Askaryan emission of neutrinos beyond $\sim$30 PeV. Surface and deep antenna stations have different benefits in terms of effective area, resolution, and the capability to reject backgrounds from cosmic-ray air showers and may be combined to reach the best sensitivity. The optimal detector configuration is still to be identified. This contribution presents the full-array simulation efforts for a combination of deep and surface antennas, and compares different design options with respect to their sensitivity to fulfil the science goals of IceCube-Gen2.

  DOI

• Time-Integrated Neutrino Source Searches with 10 Years of IceCube Data

  Physical Review Letters · 2020 · 433 citations

  • Physics
  • Particle physics
  • Nuclear physics

  This Letter presents the results from pointlike neutrino source searches using ten years of IceCube data collected between April 6, 2008 and July 10, 2018. We evaluate the significance of an astrophysical signal from a pointlike source looking for an excess of clustered neutrino events with energies typically above ∼1 TeV among the background of atmospheric muons and neutrinos. We perform a full-sky scan, a search within a selected source catalog, a catalog population study, and three stacked Galactic catalog searches. The most significant point in the northern hemisphere from scanning the sky is coincident with the Seyfert II galaxy NGC 1068, which was included in the source catalog search. The excess at the coordinates of NGC 1068 is inconsistent with background expectations at the level of 2.9σ after accounting for statistical trials from the entire catalog. The combination of this result along with excesses observed at the coordinates of three other sources, including TXS 0506+056, suggests that, collectively, correlations with sources in the northern catalog are inconsistent with background at 3.3σ significance. The southern catalog is consistent with background. These results, all based on searches for a cumulative neutrino signal integrated over the 10 years of available data, motivate further study of these and similar sources, including time-dependent analyses, multimessenger correlations, and the possibility of stronger evidence with coming upgrades to the detector.

  DOI

Recent grants

• Testing DAMA with the COSINE Experiment

  NSF · $793k · 2019–2024

• CAREER: Towards a Definitive Test of DAMA's Annual Modulation Signal

  NSF · $451k · 2014–2018

• CAREER: Towards a Definitive Test of DAMA's Annual Modulation Signal

  NSF · $408k · 2012–2014

• Feasibility Study for a Dark Matter Search co-located with the IceCube Detector in the Antarctic Ice

  NSF · $6k · 2010–2011

Frequent coauthors

• Kwok Lung Fan

  3474 shared

• S. R. Klein

  3173 shared

• S. Sarkar

  3039 shared

• W. Rhode

  3004 shared

• N. van Eijndhoven

  2997 shared

• G. M. Spiczak

  2989 shared

• M. Kowalski

  2985 shared

• G. T. Przybylski

  Lawrence Berkeley National Laboratory

  2985 shared

Education

• MS, Physics

  University of Washington

  1996

Awards & honors

• Hoffleit Scholarship
• Dorrit Hoffleit Scholars
• Yale-Palomar Remote Observing Facility
• Yale Time Allocation Committee

Similar researchers at Yale University

• Mark Gersteinh-217
• Liangbing Huh-172
• Akiko Iwasakih-145
• Alan Kazdinh-142
• Douglas L. Rothmanh-125