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Spin correlation coefficient for proton-He3 elastic scattering at 100 MeV

Physical Review C 2022年第5期106卷 054002-054002页

作者： A. Watanabe S. Nakai K. Sekiguchi A. Deltuva S. Goto K. Hatanaka Y. Hirai T. Ino D. Inomoto M. Inoue S. Ishikawa M. Itoh H. Kanda H. Kasahara Y. Maeda K. Miki K. Nonaka H. J. Ong H. Oshiro D. Sakai H. Sakai S. Shibuya D. T. Tran H. Umetsu Y. Utsuki T. Wakasa Department of Physics Tokyo Institute of Technology Tokyo 152-8551 Japan Department of Physics Tohoku University Sendai 980-8578 Japan Graduate Program on Physics for the Universe (GP-PU) Tohoku University Sendai 980-8578 Japan Institute of Theoretical Physics and Astronomy Vilnius University Saulėtekio al. 3 LT-10257 Vilnius Lithuania Department of Physics Kyushu University Fukuoka 819-0395 Japan Research Center for Nuclear Physics Osaka University Ibaraki 567-0047 Japan High Energy Accelerator Research Organization (KEK) Tsukuba 305-0801 Japan Science Research Center Hosei University Tokyo 102-8160 Japan Cyclotron and Radioisotope Center Tohoku University Sendai 980-8578 Japan Faculty of Engineering University of Miyazaki Miyazaki 889-2192 Japan Institute of Modern Physics (IMP) Chinese Academy of Sciences Lanzhou 730000 China RIKEN Nishina Center Wako 351-0198 Japan Institute of Physics Vietnam Academy of Science and Technology Hanoi 10000 Vietnam

We present the measured spin correlation coefficient Cy,y for p−He3 elastic scattering at 100 MeV at the angles θc.m.=46.9∘–149.2∘ in the center-of-mass system. The Cy,y data and the existing cross section data are compared with rigorous four-nucleon scattering calculations based on realistic nucleon-nucleon potentials. Large differences are seen in the regime around the cross section minimum for both observables. The Δ-isobar effects estimated by the NN+NΔ coupled-channels approach are small for the cross section. Meanwhile, in Cy,y, the Δ-isobar effects improve the agreement with the data. The analysis of the p−He3 elastic scattering amplitudes implies the necessity of three-nucleon forces (3NFs) that enhance the vector components in the amplitudes. The obtained results indicate that the spin correlation coefficient Cy,y expands the knowledge of the nuclear interactions with the Δ isobar or those including 3NFs that are masked in nucleon-deuteron elastic scattering.

关键词： Few-body systems H & He induced nuclear reactions Nuclear forces Nucleon-nucleon interactions

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Photon Production in High-Energy Heavy-Ion Collisions: Thermal Photons and Radiative Recombination

arXiv

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arXiv 2022年

作者： Fujii, Hirotsugu Itakura, Kazunori Miyachi, Katsunori Nonaka, Chiho Institute of Physics University of Tokyo Komaba Tokyo153-8902 Japan Nagasaki Institute of Applied Science Nagasaki851-0193 Japan KEK Theory Center IPNS KEK Tsukuba305-0801 Japan Department of Physics Nagoya University Nagoya464-8602 Japan Physics Program Graduate School of Advanced Science and Engineering Hiroshima University Higashi-Hiroshima739-8526 Japan Nagoya University Nagoya464-8602 Japan

We present a comprehensive analysis of photon production at RHIC and the LHC, proposing radiative hadronization as an additional photon source in high-energy heavy-ion collisions. For thermal photon, we perform relati... 详细信息

关键词： Heavy ions

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Radiative hadronization: Photon emission at hadronization from quark-gluon plasma

arXiv

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arXiv 2022年

作者： Fujii, Hirotsugu Itakura, Kazunori Miyachi, Katsunori Nonaka, Chiho Institute of Physics University of Tokyo Komaba Tokyo153-8902 Japan Nagasaki Institute of Applied Science Nagasaki851-0193 Japan KEK Theory Center IPNS KEK Tsukuba305-0801 Japan Department of Physics Nagoya University Nagoya464-8602 Japan Physics Program Graduate School of Advanced Science and Engineering Hiroshima University Higashi Hiroshima739-8526 Japan Nagoya University Nagoya464-8602 Japan

We investigate photon emission at the hadronization stage from a quark-gluon plasma created in relativistic heavy-ion collisions. A recombination-model picture suggests that a quark and an antiquark bind into a meson state in hadronization, which would apparently violate the energy conservation if there is nothing else involved. We consider here a hadronization process where the recombination accompanies a photon emission. This is an analog of the "radiative recombination" known in plasma physics, such as e− + p+ → H0 + γ, which occurs when an electromagnetic plasma goes back to a neutral atomic gas. The "radiative hadronization" picture will bring about (i) an enhancement of the photon yield, (ii) significant flow of photons similar to that of hadrons, and (iii) the photon transverse momentum (pT) distribution with a thermal profile whose effective temperature is given by blue-shifted temperature of quarks. Here as a simplest and phenomenological realization of the radiative hadronization, we modify the recombination model to involve a photon emission and evaluate the photon yield with this modified model. Adding this contribution to the direct photon yield along with thermal photon contribution calculated with a hydrodynamic model and a parametrized contribution of prompt photons, we study the pT spectrum and elliptic flow of the photons produced in heavy-ion collisions at RHIC and LHC energies. © 2022, CC BY-NC-ND.

关键词： Photons

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Model Selection using Baryon Acoustic Oscillations in the Final SDSS-IV Release

arXiv

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arXiv 2022年

作者： Melia, F. López-Corredoira, Martin Department of Physics The Applied Math Program Department of Astronomy The University of Arizona AZ85721 United States Instituto de Astrofísica de Canarias La Laguna TenerifeE-38205 Spain Departamento de Astrofísica Universidad de La Laguna La Laguna TenerifeE-38206 Spain

The baryon acoustic oscillation (BAO) peak, seen in the cosmic matter distribution at redshifts up to ∼ 3.5, reflects the continued expansion of the sonic horizon first identified in temperature anisotropies of the cosmic microwave background. The BAO peak position can now be measured to better than ∼ 1% accuracy using galaxies, and ∼ 1.4 − 1.6% precision with Ly-α forrests and the clustering of quasars. In conjunction with the Alcock-Paczý nski (AP) effect, which arises from the changing ratio of angular to spatial/redshift size of (presumed) spherically-symmetric source distributions with distance, the BAO measurement is viewed as one of the most powerful tools to use in assessing the geometry of the Universe. In this paper, we employ five BAO peak measurements from the final release of the Sloan Digital Sky Survey IV, at average redshifts hzi = 0.38, 0.51, 0.70, 1.48 and 2.33, to carry out a direct head-to-head comparison of the standard model, ΛCDM, and one of its principal competitors, known as the Rh = ct universe. For completeness, we complement the AP diagnostic with a volume-averaged distance probe that assumes a constant comoving distance scale rd. Both probes are free of uncertain parameters, such as the Hubble constant, and are therefore ideally suited for this kind of model selection. We find that Rh = ct is favored by these measurements over the standard model based solely on the AP effect, with a likelihood ∼ 75% versus ∼ 25%, while Planck-ΛCDM is favored over Rh = ct based solely on the volume-averaged distance probe, with a likelihood ∼ 80% versus ∼ 20%. A joint analysis using both probes produces an inconclusive outcome, yielding comparable likelihoods to both models. We are therefore not able to confirm with this work that the BAO data, on their own, support an accelerating Universe. Copyright © 2022, The Authors. All rights reserved.

关键词： Acoustic intensity measurement

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The Featherweight Giant: Unraveling the Atmosphere of a 17 Myr Planet with JWST

arXiv

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arXiv 2024年

作者： Thao, Pa Chia Mann, Andrew W. Feinstein, Adina D. Gao, Peter Thorngren, Daniel Rotman, Yoav Welbanks, Luis Brown, Alexander Duvvuri, Girish M. France, Kevin Longo, Isabella Sandoval, Angeli Christian Schneider, P. Wilson, David J. Youngblood, Allison Vanderburg, Andrew Barber, Madyson G. Wood, Mackenna L. Batalha, Natasha E. Kraus, Adam L. Murray, Catriona Anne Newton, Elisabeth R. Rizzuto, Aaron Tofflemire, Benjamin M. Tsai, Shang-Min Bean, Jacob L. Berta-Thompson, Zachory K. Evans-Soma, Thomas M. Froning, Cynthia S. Kempton, Eliza M.-R. Miguel, Yamila Sebastian Pineda, J. Department of Physics and Astronomy The University of North Carolina at Chapel Hill Chapel HillNC27599 United States Laboratory for Atmospheric and Space Physics University of Colorado Boulder UCB 600 BoulderCO80309 United States Department of Physics and Astronomy Michigan State University East LansingMI48824 United States Earth and Planets Laboratory Carnegie Institution for Science 5241 Broad Branch Road NW WashingtonDC20015 United States Department of Physics & Astronomy Johns Hopkins University BaltimoreMD United States School of Earth and Space Exploration Arizona State University TempeAZ85281 United States Center for Astrophysics and Space Astronomy University of Colorado 389 UCB BoulderCO80309 United States Department of Physics and Astronomy Vanderbilt University NashvilleTN37235 United States Department of Astrophysical and Planetary Sciences University of Colorado UCB 389 BoulderCO80309 United States Astrophysics Program The CUNY Graduate Center City University of New York New YorkNY10016 United States Exoplanets and Stellar Astrophysics Laboratory NASA Goddard Space Flight Center GreenbeltMD20771 United States Hamburger Sternwarte Gojenbergsweg 112 HamburgD-21029 Germany Department of Physics Kavli Institute for Astrophysics and Space Research Massachusetts Institute of Technology CambridgeMA02139 United States MIT Kavli Institute for Astrophysics Space Research Massachusetts Institute of Technology CambridgeMA02139 United States NASA Ames Research Center Moffett FieldCA94035 United States Department of Astronomy The University of Texas at Austin AustinTX78712 United States Department of Astrophysical and Planetary Sciences University of Colorado BoulderCO United States Department of Physics and Astronomy Dartmouth College HanoverNH03755 United States Mondo Level 26/2 Southbank Blvd SouthbankVIC3006 Australia Department of Earth and Planetary Sciences University of California RiversideCA United States

The characterization of young planets (⊕) planet, HIP 67522b, observed with JWST NIRSpec/G395H. To check for spot contamination, we obtain a simultaneous g-band transit with SOAR. The spectrum exhibits absorption features 30-50% deeper than the overall depth, far larger than expected from an equivalent mature planet, and suggests that HIP 67522 b's mass is ⊕ irrespective of cloud cover and stellar contamination. A Bayesian retrieval analysis returns a mass constraint of 13.8±1.0M⊕. This challenges the previous classification of HIP 67522b as a hot Jupiter and instead, positions it as a precursor to the more common sub-Neptunes. With a density of 3, HIP 67522 b is one of the lowest density planets known. We find strong absorption from H2O and CO2 (≥ 7σ), a modest detection of CO (3.5σ), and weak detections of H2S and SO2 ( 2σ). Comparisons with radiative-convective equilibrium models suggest supersolar atmospheric metallicities and solar-to-subsolar C/O ratios, with photochemistry further constraining the inferred atmospheric metallicity to 3×10 Solar due to the amplitude of the SO2 feature. These results point to the formation of HIP 67522b beyond the water snowline, where its envelope was polluted by icy pebbles and planetesimals. The planet is likely experiencing substantial mass loss (0.01-0.03 M⊕ Myr−1), sufficient for envelope destruction within a Gyr. This highlights the dramatic evolution occurring within the first 100 Myr of its existence. © 2024, CC BY.

关键词： Planets

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A Cluster-Based Filtering Technique for Denoising 4D-STEM Datasets

引用

Microscopy and Microanalysis 2024年第SUPPLEMENT_1期30卷

作者： Mireles, Adan Han, Yimo Applied Physics Graduate Program Smalley-Curl Institute Rice University Houston TX USA Department of Materials Science and NanoEngineering Rice University Houston TX USA

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PICOLON dark matter search project by large-volume NaI(Tl) scintillator 38

PICOLON dark matter search project by large-volume NaI(Tl) s...

引用

38th International Cosmic Ray Conference, ICRC 2023

作者： Fushimi, K. Chernyak, D. Ejiri, H. Hata, K. Hazama, R. Iida, T. Ikeda, H. Imagawa, K. Inoue, K. Ito, H. Kisimoto, T. Koga, M. Kotera, K. Kozlov, A. Nakamura, K. Orito, R. Shima, T. Takemoto, Y. Umehara, S. Urano, Y. Yamamoto, Y. Yasuda, K. Yoshida, S. Division of Science and Technology Tokushima University 2-1 Minami Josanjima-cho Tokushima Tokushima City770-8506 Japan Department of Physics and Astronomy University of Alabama TuscaloosaAL35487 United States Research Center for Nuclear Physics Osaka University 10-1 Mihogaoka Ibaraki city Osaka567-0042 Japan Research Center for Neutrino Science Tohoku University 6-3 Aramaki Aza Aoba Aobaku Miyagi Sendai city980-8578 Japan Department of Environmental Science and Technology Osaka Sangyo University 3-1-1 Nakagaito Daito city Osaka574-8530 Japan Faculty of Pure and Applied Sciences University of Tsukuba 1-1-1 Tennoudai Ibaraki Tsukuba city305-8571 Japan I.S.C. Lab. 5-15-24 Torikai Honmachi Settsu city Osaka566-0052 Japan 5-1-5 Kashiwanoha Kashiwa city Chiba277-8583 Japan Department of Physics Faculty of Science and Technology Tokyo University of Science Noda Chiba 278-8510 Japan Department of Physics Osaka University 1-1 Machikaneyama-cho Toyonaka city Osaka560-0043 Japan Graduate School of Advanced Technology and Science Tokushima University 2-1 Minami Josanajima-cho Tokushima city Tokushima770-8506 Japan Moscow115409 Russia Butsuryo College of Osaka 3-33 Ohtori Kitamachi Nishi ward Sakai city Osaka593-8328 Japan Institute for Cosmic Ray Research The University of Tokyo 5-1-5 Kashiwanoha Kashiwa city Chiba277-8583 Japan Institute for Materials Research Tohoku University 2-1-1 Katahira Aoba-ku Sendai980-8577 Japan

PICOLON (Pure Inorganic Crystal Observatory for LOw-energy Neutr(al)ino) project is developing high-purity NaI(Tl) crystals to search for WIMPs (dark matter). The XENON experiment has excluded a large region of WIMPs. However, the annual modulation of the signal reported by the DAMA/LIBRA group has not been rejected using the same target, NaI(Tl). Recently, COSINE-100 reported an annually modulating signal of the opposite phase from the data taken using a 106 kg NaI(Tl) DM detector. We plan to build a radiopure large-volume NaI(Tl) detectors to resolve the inconsistency amoung the existing observations. We have developed and confirmed methods to remove radioactive impurities in NaI(Tl) crystals. The concentration of natural potassium is less than 20 ppb, and the U, Th series are less than a few ppt. Using large detectors effectively reduces background events originating from outside of the crystal. The possibility of background reduction and prospects for cosmic dark matter searches with large NaI(Tl) crystals using ultrahigh purification techniques will be presented. © Copyright owned by the author(s) under the terms of the Creative Commons.

关键词： Sodium Iodide

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Excitation of absorbing exceptional points in the time domain

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Physical Review A 2022年第3期106卷 L031503-L031503页

作者： Asaf Farhi Ahmed Mekawy Andrea Alù Douglas Stone Department of Applied Physics Yale University New Haven Connecticut 06520 USA Photonics Initiative Advanced Science Research Center City University of New York New York New York 10031 USA Department of Electrical Engineering City College of the City University of New York New York New York 10031 USA Physics Program Graduate Center City University of New York New York New York 10016 USA Yale Quantum Institute Yale University New Haven Connecticut 06520 USA

We analyze the time-domain dynamics of resonators supporting exceptional points (EPs), at which both the eigenfrequencies and the eigenmodes associated with perfect capture of an input wave coalesce. We find that a time-domain signature of the EP is an expansion of the class of waveforms which can be perfectly captured. We show that such resonators have improved performance for storage or transduction of energy. They also can be used to convert between waveforms within this class. We analytically derive these features and demonstrate them for several examples of coupled optical resonator systems.

关键词： Classical optics Geometrical & wave optics Lasers Light-matter interaction Photonics Scattering theory Bragg structures Complex media Optical microcavities Waveguides

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Reduction of interface defects in gate-recessed GaN HEMTs by neutral beam etching

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Materials Today Advances 2024年 23卷

作者： Yu, Chia Hao Chiang, Wei Hsiang Chen, Yi-Ho Samukawa, Seiji Wuu, Dong Sing Chung, Chin-Han Hsiao, Ching-Lien Horng, Ray Hua Institute of Electronics National Yang Ming Chiao Tung University Department of Materials Science and Engineering National Chung Hsing University Graduate Degree Program of College of Electrical and Computer Engineering National Yang Ming Chiao Tung University Institute of Comunications Engineering National Yang Ming Chiao Tung University Department of Applied Materials and Optoelectronic Engineering National Chi Nan University International College of Semiconductor Technology National Yang Ming Chiao Tung University Thin Film Physics Division Department of Physics Chemistry and Biology (IFM) Linköping University

This study investigates and compares the impact of different etching techniques on the fabrication of GaN high electron mobility transistors (HEMTs) between the inductively coupled plasma reactive ion etching (ICP-RIE) and the neutral beam etching (NBE) for the gate recess. By conducting direct current analysis, it was found that devices manufactured using the NBE exhibited superior electrical performance as compared with those produced using the ICP-RIE. These enhanced electrical characteristics include a transconductance of up to 100.4 mS/mm, a threshold voltage (V_th) of −2.3 V, an on/off current ratio of 1.1 × 10⁹, a subthreshold swing (S.S.) of 99.63 mV/dec, and a remarkably low gate leakage current. Additionally, we noted varying degrees of hysteresis in the I–V characteristics were related to process disparities possibly leading to interface defects. Multi-frequency capacitance-voltage (C–V) measurements were used to identify the interface defects at the oxide/AlGaN interface of the gate. The results revealed that devices fabricated using the NBE exhibited a lower interface defect density as compared with those fabricated using the ICP-RIE, thereby elucidating the reduced hysteresis observed in the I–V characteristics. These findings indicated the significant advantages of the NBE process in the fabrication of GaN HEMTs. © 2024 The Authors

关键词： GaN HEMTs Gate recess Interface defects Multi-frequency C–V Neutral beam etching

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A broadband X-ray imaging spectroscopy in the 2030s: the FORCE mission

arXiv

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arXiv 2023年

作者： Mori, Koji Tsuru, Takeshi G. Nakazawa, Kazuhiro Ueda, Yoshihiro Watanabe, Shin Tanaka, Takaaki Ishida, Manabu Matsumoto, Hironori Awaki, Hisamitsu Murakami, Hiroshi Nobukawa, Masayoshi Takeda, Ayaki Fukazawa, Yasushi Tsunemi, Hiroshi Takahashi, Tadayuki Hornschemeier, Ann Okajima, Takashi Zhang, William W. Williams, Brian J. Venters, Tonia Madsen, Kristin Yukita, Mihoko Akamatsu, Hiroki Bamba, Aya Enoto, Teruaki Fujita, Yutaka Furuzawa, Akihiro Hagino, Kouichi Ishimura, Kosei Itoh, Masayuki Kitayama, Tetsu Kobayashi, Shogo Kohmura, Takayoshi Kubota, Aya Mizumoto, Misaki Mizuno, Tsunefumi Nakajima, Hiroshi Nobukawa, Kumiko K. Noda, Hirofumi Odaka, Hirokazu Ota, Naomi Sato, Toshiki Shidatsu, Megumi Suzuki, Hiromasa Takahashi, Hiromitsu Tanimoto, Atsushi Terada, Yukikatsu Terashima, Yuichi Uchida, Hiroyuki Uchiyama, Yasunobu Yamaguchi, Hiroya Yatsu, Yoichi Department of Applied Physics and Electronic Engineering University of Miyazaki Miyazaki889-2192 Japan Department of Physics Kyoto University Kyoto606-8502 Japan Department of Physics University of Tokyo Tokyo113-0033 Japan Department of Astronomy Kyoto University Kyoto606-8502 Japan Kanagawa252-5210 Japan Department of Physics Konan University Hyogo658-8501 Japan Department of Earth and Space Science Osaka University Osaka560-0043 Japan Department of Physics Ehime University Ehime790-8577 Japan Department of Information Science Faculty of Liberal Arts Tohoku Gakuin University Miyagi981-3193 Japan Department of Teacher Training and School Education Nara University of Education Nara630-8528 Japan Department of Physical Science Hiroshima University Hiroshima739-8526 Japan The University of Tokyo Chiba277-8583 Japan NASA’s Goddard Space Flight Center GreenbeltMD20771 United States CRESST Department of Physics Center for Space Science and Technology UMBC BaltimoreMD21250 United States The Johns Hopkins University Homewood Campus BaltimoreMD21218 United States SRON Netherlands Institute for Space Research Utrecht3584 CA Netherlands Department of Physics The University of Tokyo Tokyo113-0033 Japan Extreme natural phenomena RIKEN Hakubi Research Team Cluster for Pioneering Research RIKEN Saitama351-0198 Japan Department of Physics Tokyo Metropolitan University Tokyo192-0397 Japan Fujita Health University Aichi470-1192 Japan College of Science and Engineering Kanto Gakuin University Kanagawa236-8501 Japan Faculty of Science and Engineering Waseda University Tokyo169-8555 Japan Department of Human Environmental Science Kobe University Hyogo657-8501 Japan Department of Physics Toho University Chiba274-8510 Japan Department of Physics Tokyo University of Science Tokyo162-8601 Japan Department of Physics Tokyo University of Science Chiba278-8510 Japan Department of Electronic Information Systems Shibaura Institute of

In this multi-messenger astronomy era, all the observational probes are improving their sensitivities and overall performance. The Focusing on Relativistic universe and Cosmic Evolution (FORCE) mission, the product of a JAXA/NASA collaboration, will reach a 10 times higher sensitivity in the hard X-ray band (E > 10 keV) in comparison with any previous hard X-ray missions, and provide simultaneous soft X-ray coverage. FORCE aims to be launched in the early 2030s, providing a perfect hard X-ray complement to the ESA flagship mission Athena. FORCE will be the most powerful X-ray probe for discovering obscured/hidden black holes and studying high energy particle acceleration in our Universe and will address how relativistic processes in the universe are realized and how these affect cosmic evolution. FORCE, which will operate over 1–79 keV, is equipped with two identical pairs of supermirrors and wideband X-ray imagers. The mirror and imager are connected by a high mechanical stiffness extensible optical bench with alignment monitor systems with a focal length of 12 m. A light-weight silicon mirror with multi-layer coating realizes a high angular resolution of 00 in half-power diameter in the broad bandpass. The imager is a hybrid of a brand-new SOI-CMOS silicon-pixel detector and a CdTe detector responsible for the softer and harder energy bands, respectively. FORCE will play an essential role in the multi-messenger astronomy in the 2030s with its broadband X-ray sensitivity. Copyright © 2023, The Authors. All rights reserved.

关键词： Cadmium telluride

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