Tootfinder

Environmental Regulation of Dust and Star Formation Unveiled by Subaru Dual Narrow-band Imaging: Degree-scale Balmer Decrement Mapping across a z = 0.9 Supercluster
Zhaoran Liu, Tadayuki Kodama, Brian C. Lemaux, Mariko Kubo, Jose Manuel P\'erez-Mart\'inez, Yusei Koyama, Ichi Tanaka, Kazuki Daikuhara, Roy R. Gal, Denise Hung, Masahiro Konishi, Kosuke Kushibiki, Ronaldo Laishram, Lori M. Lubin, Kentaro Motohara, Hidenori Takahashi

Environmental Regulation of Dust and Star Formation Unveiled by Subaru Dual Narrow-band Imaging: Degree-scale Balmer Decrement Mapping across a z = 0.9 Supercluster
We present results from a dual narrow-band imaging survey targeting the CL1604 supercluster at z = 0.9 using the Subaru Telescope. By combining the NB921 filter on HSC and the NB1244 filter on SWIMS, we can detect redshifted H$α$ and H$β$ emission lines from the supercluster. This unique technique allows us to measure both star formation rates and dust extinction for a sample of 94 emission-line galaxies across the supercluster. We find that dust extinction, estimated from the Balmer decremen…

Selecting Clusters and Protoclusters via Stellar Mass Density: I. Method and tests on Mock HSC-SSP catalogs
Marcelo C. Vicentin, Pablo Araya-Araya, Laerte Sodr\'e Jr., Michael A. Strauss
https://arxiv.org/abs/2510.10735

Selecting Clusters and Protoclusters via Stellar Mass Density: I. Method and tests on Mock HSC-SSP catalogs
We present an algorithm designed to identify galaxy (proto)clusters in wide-area photometric surveys by first selecting their dominant galaxy-i.e., the Brightest Cluster Galaxy (BCG) or protoBCG-through the local stellar mass density traced by massive galaxies. We focus on its application to the Hyper Suprime-Cam Subaru Strategic Program (HSC-SSP) Wide Survey to detect candidates up to $\rm z \sim 2$. In this work, we apply the method to mock galaxy catalogs that replicate the observational con…

Structural evolution of quiescent galaxies at intermediate redshift at UV and red rest-frame wavelengths
Michele Pizzardo, Ivana Damjanov, Jubee Sohn, Margaret J. Geller
https://arxiv.org/abs/2507.10675

Structural evolution of quiescent galaxies at intermediate redshift at UV and red rest-frame wavelengths
We model the wavelength dependence of structural parameters for a mass-limited sample ($M_\star>10^{10}M_\odot$) of $\sim27,000$ quiescent galaxies with $0.2 < z < 0.6$ using $grizy$ photometry from Subaru/Hyper Suprime-Cam and dense spectroscopy from the HectoMAP survey. Based on Sérsic profile fits in all five bands, we estimate the circularized half-light radius $R_{e,c}$ and Sérsic index $n$ in two rest-frames: UV (3500 Å) and red (7000 Å). Combined with $M_\star$, $z$, and D$_n4000$, $…

Detecting Sterile Neutrino Dark Matter at MeV Gamma-Ray Observatories
Subaru Fujisawa, Tatsuya Hayashi, Shigeki Matsumoto, Yuki Watanabe
https://arxiv.org/abs/2508.08695 https:/…

Detecting Sterile Neutrino Dark Matter at MeV Gamma-Ray Observatories
We explore the indirect detection of sterile neutrino dark matter within the gauged $U(1)_{B-L}$ extension of the Standard Model, in which three right-handed neutrinos account for neutrino masses, the baryon asymmetry, and dark matter. Focusing on the MeV mass range, we investigate two decay channels: the radiative decay $N \to νγ$, which produces a monochromatic photon, and the three-body decay $N \to e^- e^+ ν$, which leads to a 511 keV photon signal from positronium decay. Taking the upco…

Generalized Bishop frames of regular time-like curves in 4-dimensional Lorentz space $\mathbb{L}^{4}$
Subaru Nomoto
https://arxiv.org/abs/2510.09345 https://

Generalized Bishop frames of regular time-like curves in 4-dimensional Lorentz space $\mathbb{L}^{4}$
We introduced generalized Bishop frames on curves in 4-dimensional Euclidean space $\mathbb{E}^{4}$, which are orthonormal frames such that the derivatives of the vectors of the frames along the curve can be expressed, via a certain matrix, as a linear combination of the vectors of the frame. In relation to that, we study generalized Bishop frames of regular time-like curves. In a previous work, we showed that there is a hierarchy among different types of generalized Bishop frames for regular…

The Subaru-Asahi StarCam: Description of the system
Ichi Tanaka, Masanobu Higashiyama, Masayo Nakajima, Toyokazu Uda, Hitoshi Hasegawa, Mikiya Sato, Jun-ichi Watanabe
https://arxiv.org/abs/2508.00245

The Subaru-Asahi StarCam: Description of the system
The Subaru-Asahi StarCam is a high-sensitivity live-streaming camera for meteor observation, installed on the dome of the Subaru Telescope at the summit area of Maunakea, Hawai'i. Although it was originally intended to share the Maunakea night sky with the public, including the local Hawai'i community, the system quickly demonstrated its potential for scientific research, owing to its highly sensitive video capabilities and the exceptional fraction of clear nights at the site. The core of the S…

A Possible Shutting-Down Event of Mass Accretion in An Active Galactic Nucleus at z~1.8
Tomoki Morokuma, Malte Schramm, Toshihiro Kawaguchi, Josefa Becerra Gonz\'alez, Jose Antonio Acosta-Pulido, Nieves Castro-Rodr\'iguez, Kana Morokuma-Matsui, Shintaro Koshida, Junko Furusawa, Hisanori Furusawa, Tsuyoshi Terai, Fumi Yoshida, Kotaro Niinuma, Yoshiki Toba

A Possible Shutting-Down Event of Mass Accretion in An Active Galactic Nucleus at z~1.8
We present the discovery of a large gradual apparent fading event in optical and near-infrared wavelengths in a quasar at z=1.767 by a factor of 20-30 (in optical) over a period of ~20 years in the observed frame. This pronounced fading trend in brightness was first identified by comparing the magnitudes measured in the Subaru/Hyper Suprime-Cam (HSC) images with those in the Sloan Digital Sky Survey (SDSS) images for ~3x10^4 quasars spectroscopically identified by SDSS. We performed follow-up o…

Unveiling the Atmosphere of HR 7672 B from the Near-Infrared High-Resolution Spectrum Using REACH/Subaru
Yui Kasagi, Yui Kawashima, Hajime Kawahara, Takayuki Kotani, Kento Masuda, Kyohoon Ahn, Olivier Guyon, Teruyuki Hirano, Nemanja Jovanovic, Masayuki Kuzuhara, Julien Lozi, Motohide Tamura, Taichi Uyama, Sebastien Vievard, Kenta Yoneta
https://

Unveiling the Atmosphere of HR 7672 B from the Near-Infrared High-Resolution Spectrum Using REACH/Subaru
Characterizing the atmospheres of exoplanets and brown dwarfs is crucial for understanding their atmospheric physics and chemistry, searching for biosignatures, and investigating their formation histories. Recent advances in observational techniques, combining adaptive optics with high-resolution spectrographs, have enabled detailed spectroscopic analysis for directly imaged faint companions. In this paper, we report an atmospheric retrieval on the L-type brown dwarf HR 7672 B using a near-infr…

Direct Imaging Explorations for Companions from the Subaru/IRD Strategic Program II; Discovery of a Brown-dwarf Companion around a Nearby mid-M~dwarf LSPM~J1446 4633
Taichi Uyama, Masayuki Kuzuhara, Charles Beichman, Teruyuki Hirano, Takayuki Kotani, Qier An, Timothy D. Brandt, Markus Janson, Dimitri Mawet, Mayuko Mori, Bun'Ei Sato, Denitza Stoeva, Motohide Tamura, Masataka Aizawa, Bryson Cale, Thomas Henning, Hiroyuki Tako Ishikawa, Norio Narita, Masahiro Ogihara, Aniket Sanghi, T…

Direct Imaging Explorations for Companions from the Subaru/IRD Strategic Program II; Discovery of a Brown-dwarf Companion around a Nearby mid-M~dwarf LSPM~J1446+4633
We report the discovery of a new directly-imaged brown dwarf companion with Keck/NIRC2+pyWFS around a nearby mid-type M~dwarf LSPM~J1446+4633 (hereafter J1446). The $L'$-band contrast ($4.5\times10^{-3}$) is consistent with a $\sim20-60\ M_{\rm Jup}$ object at 1--10~Gyr and our two-epoch NIRC2 data suggest a $\sim30\%$ ($\sim3.1σ)$ variability in its $L'$-band flux. We incorporated Gaia DR3 non-single-star catalog into the orbital fitting by combining the Subaru/IRD RV monitoring results, NIRC…

A Bibliometric Analysis of the Scholarly Impact of Early Subaru Telescope-based Publications
Hideaki Fujiwara
https://arxiv.org/abs/2508.18623 https://arxi…

A Bibliometric Analysis of the Scholarly Impact of Early Subaru Telescope-based Publications
Bibliometric methods provide valuable tools for assessing scientific productivity and impact across disciplines, yet their application in astronomy journals remains relatively limited. This study conducts a bibliometric analysis of Japanese astronomy publications before and after the commissioning of the Subaru Telescope, a major national investment in observational infrastructure. Using data from Scopus and SciVal, we examine peer-reviewed journal articles published between 1996 and 2007 by au…

Oi! People my age, listen up.
When you see a kid wearing a band t-shirt, it's not time for you to play band police and ask them to name 3 songs by the band.
Instead, why not engage with them and ask them what their favorite song by that band is.
Or suggest they check out this other, similar band they may not be familiar with.
The Name 3 songs by that band joke is TIRED and not done elsewhere.
I drive Subaru. "Name 3 other cars they make!"
I l…

Cosmology from a joint analysis of second and third order shear statistics with Subaru Hyper Suprime-Cam Year 3 data
Sunao Sugiyama, Rafael C. H. Gomes, Bhuvnesh Jain
https://arxiv.org/abs/2508.14019

Cosmology from a joint analysis of second and third order shear statistics with Subaru Hyper Suprime-Cam Year 3 data
We present a joint cosmological analysis of the two-point correlation function and the aperture-mass skewness measured from the Year 3 data of the Hyper Suprime-Cam Subaru Strategic Program (HSC-Y3). The aperture-mass skewness is a compressed representation of three-point shear information, designed to capture non-Gaussian features while keeping the data vector computationally tractable. We find that including the aperture-mass skewness improves the $S_8$-$Ω_m$ figure of merit by 80% compared …

Crosslisted article(s) found for cs.DL. https://arxiv.org/list/cs.DL/new
[1/1]:
- A Bibliometric Analysis of the Scholarly Impact of Early Subaru Telescope-based Publications
Hideaki Fujiwara

First Constraints from Marked Angular Power Spectra with Subaru Hyper Suprime-Cam Survey First-Year Data
Jessica A. Cowell, Joaquin Armijo, Leander Thiele, Gabriela A. Marques, Camila P. Novaes, Daniela Grand\'on, Sihao Cheng, Masato Shirasaki, David Alonso, Jia Liu
https://arxiv.org/abs/2507.12315

First Constraints from Marked Angular Power Spectra with Subaru Hyper Suprime-Cam Survey First-Year Data
We present the first application of marked angular power spectra to weak lensing data, using maps from the Subaru Hyper Suprime-Cam Year 1 (HSC-Y1) survey. Marked convergence fields, constructed by weighting the convergence field with non-linear functions of its smoothed version, are designed to encode higher-order information while remaining computationally tractable. Using simulations tailored to the HSC-Y1 data, we test three mark functions that up- or down-weight different density environme…

Machine Learning Techniques to Distinguish Giant Stars from Dwarf Stars Using Only Photometry -- Pushing Redwards
Keyi Ding, Carrie Filion, Rosemary F. G. Wyse, Evan N. Kirby, Itsuki Ogami, Masashi Chiba, Yutaka Komiyama, L\'aszl\'o Dobos, Alexander S. Szalay
https://arxiv.org/abs/2510.07005

Machine Learning Techniques to Distinguish Giant Stars from Dwarf Stars Using Only Photometry -- Pushing Redwards
We present our photometric method, which combines Subaru/HSC $NB515$, g, and i band filters to distinguish giant stars in Local Group galaxies from Milky Way dwarf contamination. The $NB515$ filter is a narrow-band filter that covers the MgI+MgH features at $5150$ Å, and is sensitive to stellar surface gravity. Using synthetic photometry derived from large empirical stellar spectral libraries, we model the $NB515$ filter's sensitivity to stellar atmospheric parameters and chemical abundances. …

Potassium abundances in extremely metal poor stars: Implications for nucleosynthesis in the final stages of massive star evolution
M. N. Ishigaki, N. Tominaga, W. Aoki, T. Takiwaki, K. Nakamura, N. Iwamoto, K. Nomoto, C. Kobayashi
https://arxiv.org/abs/2508.20484

Potassium abundances in extremely metal poor stars: Implications for nucleosynthesis in the final stages of massive star evolution
We present a potassium (K) abundance analysis in extremely metal-poor (EMP) stars based on high-resolution ($R\sim 60000$) spectra obtained with the High Dispersion Spectrograph on the Subaru Telescope, covering the K I resonance lines at 766 and 769 nm. One-dimensional local thermodynamic equilibrium (LTE) abundances of K and other elements, including Na, Mg, Ca, Ti, Cr, and Ni, were derived using spectral synthesis. Non-local thermodynamic equilibrium (NLTE) corrections were applied to the K …

VLT/MUSE Detection of the AB Aurigae b Protoplanet with $H _{\rm \alpha}$ Spectroscopy
Thayne Currie, Jun Hashimoto, Yuhiko Aoyama, Ruobing Dong, Misato Fukagawa, Takayuki Muto, Erica Dykes, Mona El Morsy, Motohide Tamura
https://arxiv.org/abs/2508.18351

VLT/MUSE Detection of the AB Aurigae b Protoplanet with $H _{\rm α}$ Spectroscopy
We analyze high-contrast, medium-spectral-resolution $H_{\rm α}$ observations of the star AB Aurigae using the Very Large Telescope's Multi Unit Spectroscopic Explorer (MUSE). In multiple epochs, MUSE detects the AB Aur b protoplanet discovered from Subaru/SCExAO data in emission at wavelengths slightly blue-shifted from the $H_{\rm α}$ line center (i.e. at 6558.88--6560.13 Å; $\sim$ -100 km s$^{-1}$) and in absorption at redshifted wavelengths (6562.8--6565.1 Å; $\sim$ 75 km s$^{-1}$). AB …

Chemical abundances of seven stars in the GD-1 stream
Jing-Kun Zhao, Guang-Wei Li, Wako Aoki, Gang Zhao, Guo-Chao Yang, Jian-Rong Shi, Hai-Ning Li, Tadafumi Matsuno, Miho Ishigaki, Takuma Suda, Satoshi Honda, Yu-Qin Chen, Qian-Fan Xing, Hong-Liang Yan, Yong Yang, Xian-Hao Ye
https://arxiv.org/abs/2508.00671…

Chemical abundances of seven stars in the GD-1 stream
We present the first detailed chemical abundances for seven GD-1 stream stars from Subaru/HDS spectroscopy. Atmospheric parameters were derived via color calibrations ($T\rm_{eff}$) and iterative spectroscopic analysis. LTE abundances for 14 elements ($α$, odd-Z, iron-peak, n-capture) were measured. Six stars trace the main orbit, one resides in a `blob'. All exhibit tightly clustered metallicities ([Fe/H] = -2.38, {\bf intrinsic dispersion smaller than 0.05 dex, average uncertainty is about 0…

Crosslisted article(s) found for astro-ph.EP. https://arxiv.org/list/astro-ph.EP/new
[1/1]:
- Direct Imaging Explorations for Companions from the Subaru/IRD Strategic Program II; Discovery of...
Taichi Uyama, et al.

SDSS-C4 3028: The Nearest Blue Galaxy Cluster Devoid of an Intracluster Medium
Shweta Jain, Yuanyuan Su, Andra Stroe, Paul Nulsen, Hyejeon Cho, Kim HyeongHan, M. James Jee, Ralph P. Kraft, Scott Randall, Jimmy A. Irwin, Ryan L. Sanders, Christine Jones
https://arxiv.org/abs/2509.22523

SDSS-C4 3028: The Nearest Blue Galaxy Cluster Devoid of an Intracluster Medium
SDSS-C4 3028 is a galaxy cluster at $z=0.061$, notable for its unusually high fraction of star-forming galaxies with 19 star-forming and 11 quiescent spectroscopically-confirmed member galaxies. From Subaru/HSC imaging, we derived a weak lensing mass of $M_{200} = (1.3 \pm 0.9) \times 10^{14} \rm M_\odot$, indicating a low-mass cluster. This is in excellent agreement with its dynamical mass of $M_{200} = (1.0\pm0.4)\times10^{14} \rm M_\odot$, derived from SDSS spectroscopic data. XMM-Newton obs…

The Extended Stellar Distribution in the Outskirts of the Ursa Minor Dwarf Spheroidal Galaxy
Kyosuke S. Sato, Sakurako Okamoto, Masafumi Yagi, Yutaka Komiyama, Nobuo Arimoto, Rosemary F. G. Wyse, Evan N. Kirby, Masashi Chiba, Itsuki Ogami, Mikito Tanaka
https://arxiv.org/abs/2509.20914

The Extended Stellar Distribution in the Outskirts of the Ursa Minor Dwarf Spheroidal Galaxy
We discover an extended distribution of main-sequence (MS) stars along the minor axis of the Ursa Minor (UMi) dwarf spheroidal galaxy (dSph). This study is enabled by deep, wide Subaru/Hyper Suprime-Cam data, reaching photometric uncertainties below 0.1 mag at $g,i \sim 26$ mag. Color-magnitude diagrams along the major and minor axes reveal a clear excess of MS stars beyond the nominal tidal radius along the minor axis. To characterize this structure, we derive radial number density profiles in…

Analysing the prevalence of tidal features in HSC-SSP using self-supervised representation learning
A. Desmons, S. Brough, F. Lanusse, L. Canepa, A. Khalid
https://arxiv.org/abs/2509.18274

A Metal-Free Galaxy at $z = 3.19$? Evidence of Late Population III Star Formation at Cosmic Noon
Sijia Cai, Mingyu Li, Zheng Cai, Yunjing Wu, Fujiang Yu, Mark Dickinson, Fengwu Sun, Xiaohui Fan, Ben Wang, Fergus Cullen, Fuyan Bian, Xiaojing Lin, Jiaqi Zou
https://arxiv.org/abs/2507.17820

A Metal-Free Galaxy at $z = 3.19$? Evidence of Late Population III Star Formation at Cosmic Noon
Star formation from metal-free gas, the hallmark of the first generation of Population III stars, was long assumed to occur in the very early Universe. We report the discovery of MPG-CR3 (Metal-Pristine Galaxy COSMOS Redshift 3; hereafter CR3), an extremely metal-poor galaxy at redshift $z= 3.193\pm0.016$. From JWST, VLT, and Subaru observations, CR3 exhibits exceptionally strong Ly$α$, H$α$, and He I $λ$10830 emission. We measure rest-frame equivalent widths of EW$_0$(Ly$α$) $\approx822$ A…