Telescope Array Collaboration, R. U. Abbasi, M. Abe, T. Abu-Zayyad, M. Allen, Y. Arai, E. Barcikowski, J. W. Belz, D. R. Bergman, S. A. Blake, R. Cady, B. G. Ch… 展开作者
Telescope Array Collaboration, R. U. Abbasi, M. Abe, T. Abu-Zayyad, M. Allen, Y. Arai, E. Barcikowski, J. W. Belz, D. R. Bergman, S. A. Blake, R. Cady, B. G. Cheon, J. Chiba, M. Chikawa, T. Fujii, K. Fujisue, K. Fujita, R. Fujiwara, M. Fukushima, R. Fukushima, G. Furlich, W. Hanlon, M. Hayashi, N. Hayashida, K. Hibino, R. Higuchi, K. Honda, D. Ikeda, T. Inadomi, N. Inoue, T. Ishii, H. Ito, D. Ivanov, H. Iwakura, H. M. Jeong, S. Jeong, C. C. H. Jui, K. Kadota, F. Kakimoto, O. Kalashev, K. Kasahara, S. Kasami, H. Kawai, S. Kawakami, S. Kawana, K. Kawata, E. Kido, H. B. Kim, J. H. Kim, J. H. Kim, M. H. Kim, S. W. Kim, Y. Kimura, S. Kishigami, V. Kuzmin, M. Kuznetsov, Y. J. Kwon, K. H. Lee, B. Lubsandorzhiev, J. P. Lundquist, K. Machida, H. Matsumiya, T. Matsuyama, J. N. Matthews, R. Mayta, M. Minamino, K. Mukai, I. Myers, S. Nagataki, K. Nakai, R. Nakamura, T. Nakamura, Y. Nakamura, T. Nonaka, H. Oda, S. Ogio, M. Ohnishi, H. Ohoka, Y. Oku, T. Okuda, Y. Omura, M. Ono, R. Onogi, A. Oshima, S. Ozawa, I. H. Park, M. S. Pshirkov, J. Remington, D. C. Rodriguez, G. I. Rubtsov, D. Ryu, H. Sagawa, R. Sahara, Y. Saito, N. Sakaki, T. Sako, N. Sakurai, K. Sano, K. Sato, T. Seki, K. Sekino, P. D. Shah, F. Shibata, N. Shibata, T. Shibata, H. Shimodaira, B. K. Shin, H. S. Shin, D. Shinto, J. D. Smith, P. Sokolsky, N. Sone, B. T. Stokes, T. A. Stroman, T. Suzawa, Y. Takagi, Y. Takahashi, M. Takamura, M. Takeda, R. Takeishi, A. Taketa, M. Takita, Y. Tameda, H. Tanaka, K. Tanaka, M. Tanaka, Y. Tanoue, S. B. Thomas, G. B. Thomson, P. Tinyakov, I. Tkachev, H. Tokuno, T. Tomida, S. Troitsky, R. Tsuda, Y. Tsunesada, Y. Uchihori, S. Udo, T. Uehama, F. Urban, T. Wong, K. Yada, M. Yamamoto, K. Yamazaki, J. Yang, K. Yashiro, F. Yoshida, Y. Zhezher, Z. Zundel
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26 pages, 17 figures, submitted to Nuclear Inst. and Methods in Physics Research, A
Telescope Array (TA) is the largest ultrahigh energy cosmic-ray (UHECR) observatory in the Northern Hemisphere. It explores the origin of UHECRs by measuring their energy spectrum, arrival-direction distribution, and mass composition using a surface detector (SD) array covering approximately 700 km$^2$ and fluorescence detector (FD) stations. TA has found evidence for a cluster of cosmic rays with energies greater than 57 EeV. In order to confirm this evidence with more data, it is necessary to increase the data collection rate.We have begun building an expansion of TA that we call TAx4. In this paper, we explain the motivation, design, technical features, and expected performance of the TAx4 SD. We also present TAx4's current status and examples of the data that have already been collected.
Knowledge of the mass composition of ultra-high-energy cosmic rays is understood to be a salient component in answering the open questions in the field. The AugerPrime upgrade of the Pierre Auger Observatory aims to enhance its surface detector with the hardware necessary to reconstruct primary mass for individual events. This involves placing a scintillation-based detector with an active area of $3.8 \,\mathrm{m}^2$ on top of each existing water-Cherenkov detector in its surface detector array. Here, we present the methods for simulating this Scintillator Surface Detector. These simulations h…
We demonstrate single electron-hole pair resolution in a single-sided, contact-free 1 cm$^2$ by 1 mm thick Si crystal operated at 48 mK, with a baseline energy resolution of 3 eV. This crystal can be operated at voltages in excess of $\pm50$ V, resulting in a measured charge resolution of 0.06 electron-hole pairs. The high aluminum coverage ($\sim$70%) of this device allows for the discrimination of surface events and separation of events occurring near the center of the detector from those near the edge. We use this discrimination ability to show that non-quantized dark events seen in previou…
A technique using layered wavelength shifting, scintillating and non-scintillating films is presented to achieve discrimination of surface $α$ events from low-energy nuclear recoils in liquid argon detectors. A discrimination power greater than $10^{8}$, similar to the discrimination possible for electronic recoils in argon, can be achieved by adding a 50 micron layer of scintillator with a suitably slow decay time, approximately 300 ns or greater, to a wavelength-shifter coated surface. The technique would allow suppression of surface $α$ events in a very large next-generation argon dark matt…
A potential source of dominant backgrounds for many rare-event searches or screening detectors is from radon daughters, specifically $^{210}$Pb, deposited on detector surfaces, often during detector fabrication. Performing a late-stage etch is challenging because it may damage the detector. This paper describes a late-stage etching technique that reduces surface $^{210}$Pb and $^{210}$Po by $>99\times$ at 90% C.L.
Long-lived radon daughters are a critical background source in experiments searching for low-energy rare events. Originating from radon in ambient air, radioactive polonium, bismuth and lead isotopes plate-out on materials that are later employed in the experiment. In this paper, we examine cleaning procedures for their capability to remove radon daughters from PTFE surfaces, a material often used in liquid xenon TPCs. We found a large difference between the removal efficiency obtained for the decay chains of $^{222}$Rn and $^{220}$Rn, respectively. This indicates that the plate-out mechanism …
Recent results from the SENSEI experiment show that a cut on event clustering can reduce low-energy excesses in their eV-sensitive calorimeter. This hints at the role of surrounding uninstrumented surfaces in producing backgrounds. Charged particles crossing dielectric boundaries are well known to produce low-energy radiation. In particular, transition radiation, secondary electron emission, and sputtering may contribute to the spectrum, morphology, and rate of events observed in eV-sensitive detectors. The rich phenomenology and high yields of these surface processes will complicate compariso…
An upgrade of the present IceCube surface array (IceTop) with scintillation detectors and possibly radio antennas is foreseen. The enhanced array will calibrate the impact of snow accumulation on the reconstruction of cosmic-ray showers detected by IceTop as well as improve the veto capabilities of the surface array. In addition, such a hybrid surface array of radio antennas, scintillators and Cherenkov tanks will enable a number of complementary science targets for IceCube such as enhanced accuracy to mass composition of cosmic rays, search for PeV photons from the Galactic Center, or more th…
The IceCube Neutrino Observatory at the South Pole is a multi-component particle detector consisting of the IceTop surface array and the deep in-ice IceCube array. The foreseen enhancement of the surface instrumentation will consist of plastic scintillator panels read out by silicon photomultipliers. This additional detector component will calibrate the effect of snow accumulation on the IceTop tanks, improve the measurement of cosmic rays, and enhance the atmospheric background rejection for the high-energy astrophysical neutrino detection. Two scintillator prototype stations were deployed at…
The next generation of the IceCube Neutrino Observatory, IceCube-Gen2, will constitute a much larger detector, increasing the rate of high-energy neutrinos. IceCube-Gen2 will address the long-standing questions about astrophysical accelerators. The experiment will also include a surface air-shower detector which will allow for measurements of cosmic rays in the energy region where a transition between Galactic and extragalactic accelerators is expected. As a baseline design for the surface detector, we consider a surface array above the optical in-ice array consisting of the same type of stati…
The SPHERE-2 balloon-borne detector designed for extensive air shower (EAS) observations using EAS optical Vavilov-Cherenkov radiation (``Cherenkov light''), reflected from the snow-covered surface of Lake Baikal is described. We briefly discuss the concept behind the reflected Cherenkov light method, characterize the conditions at the experimental site and overview the construction of the tethered balloon used to lift the SPHERE-2 telescope above the surface. This paper is mainly dedicated to a detailed technical description of the detector, including its optical system, sensitive elements, e…
The ARIANNA detector aims to detect neutrinos with energies above \SI{e16}{eV} by instrumenting 0.5 Teratons of ice with a surface array of a thousand independent radio detector stations in Antarctica. The Antarctic ice is transparent to the radio signals caused by the Askaryan effect which allows for a cost-effective instrumentation of large volumes. Several pilot stations are currently operating successfully at the Moore's Bay site (Ross Ice Shelf) and at the South Pole. As the ARIANNA detector stations are positioned at the surface, the more abundant cosmic-ray air showers are also measured…
Higher-order Laguerre-Gauss (LG) modes have previously been investigated as a candidate for reducing test-mass thermal noise in ground-based gravitational-wave detectors like Advanced LIGO. It has been shown however that LG modes' fragility against mirror surface figure imperfections limits their compatibility with the current state-of-the-art test masses. In this paper we explore the alternative of using higher-order Hermite-Gauss (HG) modes for thermal noise reduction, and show that with the deliberate addition of astigmatism they are orders of magnitude more robust against mirror surface di…
The extremely low flux of ultra-high energy cosmic rays (UHECR) makes their direct observation by orbital experiments practically impossible. For this reason all current and planned UHECR experiments detect cosmic rays indirectly by observing the extensive air showers (EAS) initiated by cosmic ray particles in the atmosphere. The world largest statistics of the ultra-high energy EAS events is recorded by the networks of surface stations. In this paper we consider a novel approach for reconstruction of the arrival direction of the primary particle based on the deep convolutional neural network.…
IceTop, the surface array of the IceCube Neutrino Observatory, consists of 162 ice-Cherenkov tanks distributed over an area of 1km$^2$. Besides being used as a veto for the in-ice neutrino detector, IceTop is a powerful cosmic-ray detector. In the upcoming years, the capabilities of the IceTop array will be enhanced by augmenting the existing ice-Cherenkov tanks with an array of elevated scintillator panels and radio antennas. Combining the data obtained from the different detectors will improve the reconstruction of cosmic-ray energy and primary mass while reducing the energy threshold and in…
IceCube-Gen2, the extension of the IceCube Neutrino Observatory, will feature three main components: an optical array in the deep ice, a large-scale radio array in the shallow ice and firn, and a surface detector above the optical array. Thus, IceCube-Gen2 will not only be an excellent detector for PeV neutrinos, but also constitutes a unique setup for the measurement of cosmic-ray air showers, where the electromagnetic component and low-energy muons are measured at the surface and high-energy muons are measured in the ice. As for ongoing enhancement of IceCube's current surface array, IceTop,…
IceAct is a proposed surface array of cost effective and compact Silicon Photomultipliers (SiPM) based small-size (50 cm) Imaging Air Cherenkov Telescopes above the IceCube in-ice detector. In coincidence with the in-ice and surface components of IceCube it forms a hybrid detector that enables new measurements combining the information from the Cherenkov light image, the surface particle footprint and the in-ice muon tracks of extensive air showers. During January 2019, two new versions of the IceAct telescope demonstrators featuring 61 SiPM pixels and improved optics were installed in the cen…
Reconstruction of the depth of the shower maximum of air showers with the SD-750 surface detector of the Pierre Auger Observatory using neural networks
