Peer Revenue Equity in science

Papers

Fresh from arXiv, typeset properly. Highlighted words trade on the market.

Physics Astrophysics

astro-ph Watch Astrophysics

Monday 22 December

Instrumentation and Methods for Astrophysics

Towards DM-free search for Fast Radio Bursts with Machine Learning – I. An implementation on multibeam data

Yao Chen, Rui Luo, Chen Wang et al. (+13 more)

Searching for fleeting radio transients like fast radio bursts (FRBs) with wide-field radio telescopes has become a common challenge in data-intensive science. Conventional algorithms normally cost enormous time to seek candidates by finding the correct dispersion measures, of which the process is so-called dedispersion. Here we present a novel scheme to identify FRB signals from raw data without dedispersion using Machine Learning (ML). Under the data environment for multibeam receivers, we train the EfficientNet model and achieve both exceeding 92% accuracy and precision in FRB recognition. We find that the searching efficiency can be significantly enhanced without the procedure of dedispersion compared with conventional softwares like TransientX and presto. Specifically, the impact of radio frequency interference (RFI) for single-beam and multibeam data has been investigated, and we find ML can naturally mitigate RFI under the multibeam environment. Finally, we validate the trained model on actual data from the current FRB surveys carried out by the Five-hundred-meter Aperture Spherical radio Telescope, which provides considerable potential for real implementation in the future.
Read the full abstract

All authors Yao Chen, Rui Luo, Chen Wang, Yong-Kun Zhang, Shiqian Zhao, Chengbing Lyu, ZePeng Zheng, Hai Lei, DeJiang Zhou, Chenhui Niu, JinLin Han, George Hobbs, Di Li, Chengwei Liang, Siyi Tan, Ting Tian

Astrophysics of Galaxies

Dynamically close galaxy pairs from the unWISE survey: Testing the merger-AGN-star formation connection

Josephine Chishala, Roberto De Propris and Mirjana Pović

Galaxy mergers are expected to have a profound influence on the star formation histories of galaxies. It is generally expected that mergers are the main drivers of galaxy mass growth through the accretion of mass and the triggering of new star formation episodes, while the shocks and torques induced by the merger may drive gas and dust to central supermassive black holes and fuel active galactic nuclei (AGN) activity and producing both positive and negative feedback. We test whether a merger-AGN-star formation connection exists by selecting samples of galaxy pairs of stellar masses log(M/Msun) approximately 10.2 and 11.4 within the redshift of 0.25 at various projected separation and velocity differences in an increasing order, and therefore having a decreasing probability of being truly bound and interacting. We identify galaxies in close pairs and then measure their star formation rates (SFRs) (via their NUV - r colours) and the degree of AGN activity (from X-rays, radio emission at 20cm, WISE infrared colours, and emission line ratios) as a function of their projected separation and velocity difference. We find only weak evidence that galaxies in pairs have higher SFRs as galaxies become closer in projected and velocity separation, except possibly for pairs at closest separation of less than 20 kpc and velocity difference less than 500 km/s. Similarly, we see no strong evidence that AGN are more common for galaxies in closer pairs, irrespective of the method used to detect AGN. For this sample, we do not find any clear evidence that mergers and interactions may play a significant role in triggering star formation and AGN activity, opposite to expectations from theoretical models invoking feedback episodes. Secular processes may be more important, although this may depend on the selection of galaxies and indicators for star formation and AGN activity.
Read the full abstract

High Energy Astrophysical Phenomena

Identifying Quasi-Periodic Micropulses in Pulsars with FAST Using Convolutional Neural Networks

Shidong Wang, Hui Liu, Ru-Shuang Zhao et al. (+12 more)

Quasi-periodic MicroPulses (QMP) are quasi-periodic microstructural features manifested in individual pulsar radio pulses, the study of which is crucial for understanding pulsar radiation mechanisms. Manual identification of QMP in large-scale pulsar single-pulse datasets remains highly inefficient. To address this, we propose a Dual-Stage Residual Network (DSR) that achieves automated QMP detection in FAST observational data through joint analysis of single-pulse profiles and their Amplitude Distribution Profiles (ADP), defined as the power spectra of the autocorrelation function derivatives of the microstructure residuals. The model was trained on PSR B1933+16 data from 2019 (10,486 single pulses) and evaluated on manually annotated PSR B1933+16 data from 2020 (9,657 single pulses). DSR achieved 96.10% recall and 95.85% precision on the test set. This approach provides an automated pipeline for large-scale, reproducible QMP identification and establishes the foundation for in-depth investigation of their physical mechanisms.
Read the full abstract

All authors Shidong Wang, Hui Liu, Ru-Shuang Zhao, Baoqiang Lao, Yong-Kun Zhang, Y.F. Xiao, Pei Wang, Di Li, R.W. Tian, Z.F. Tu, Q. Zhou, Z.J. Zhang, Qijun Zhi, Shijun Dang, Kun Yang

Earth and Planetary Astrophysics

Disentangling the hemispheres of Teegarden's Star b with LIFE

Ryan Boukrouche and Markus Janson

Teegarden's Star is one of the most promising targets for the first observations of LIFE, as a non-transiting rocky planet with similar bulk properties to the Earth, and a relatively quiescent M-dwarf host star. We use LIFEsim, a software developed by the ETH LIFE team, along with thermal emission maps obtained from a suite of three-dimensional global climate model (GCM) simulations, to explore the sensitivity of LIFE to the observation geometry. We find that 3 days of observation in broadband would be enough to disentangle the hemispheres of the planet with a 1{\sigma} or 3{\sigma} confidence level with a baseline or optimistic scenario respectively. Doing the same for a fast-rotator in the habitable zone of a G-class star would be prohibitively challenging. Given enough observation time, the sensitivity of LIFE may allow some spatial resolution of Teegarden's Star b to be achieved, which may directly link to the presence of water clouds and therefore an active hydrology.
Read the full abstract

Earth and Planetary Astrophysics

Orbital Stability of Moons Around the TRAPPIST-1 Planets

Shubham Dey and Sean N. Raymond

We investigate the dynamical stability of potential satellites orbiting the seven planets of the TRAPPIST-1 system using a suite of $N$-body simulations. For each planet, we show that moons can remain stable from the Roche limit out to near the theoretical prograde stability boundary at roughly $0.5$ Hill Radii. We quantify how perturbations from neighbouring planets modify these stability limits. Although the overall effect of individual perturbers is generally weak, the combined gravitational influence of the full multi-planet configuration produces a modest contraction of the outer stable radius, notably for TRAPPIST-1 b and TRAPPIST-1 e. For each of the seven planets, the outer stability limit for satellites is at 40-45% of the Hill radius, consistent with previous work. Using simple long-term tidal decay calculations, we show that the most massive satellites that could survive over Gyr timescales are $10^{-(7-9)} M_\oplus$ (with higher possible masses for the outer planets).
Read the full abstract

High Energy Astrophysical Phenomena

Multi-wavelength study of the pre-eruption dip in the recurrent nova T Coronae Borealis preceding imminent nova eruption

Songpeng Pei, Xiaowan Zhang, Renzhi Su et al. (+6 more)

We present a multi-wavelength study of the symbiotic recurrent nova (RN) T Coronae Borealis (T CrB) using Swift Burst Alert Telescope (BAT) / X-Ray Telescope (XRT) / UltraViolet Optical Telescope (UVOT) and American Association of Variable Stars Observers (AAVSO) observations from 2005 to 2025. Our analysis spans quiescent, high, and pre-eruption dip states. We find that brightening amplitudes increase toward shorter wavelengths in both optical and UV bands, while the UV and X-ray fluxes are generally anti-correlated throughout all phases. During the 2023-2024 pre-eruption dip, soft and hard X-rays increased as optical and ultraviolet (UV) brightness declined, consistent with a transition from an optically thick to thin boundary layer driven by a reduction in the accretion rate. We also report, for the first time, a second, lower-amplitude dip occurring between September 2024 and February 2025 following the primary 2023-2024 pre-eruption dip. The observed variability supports an accretion-variation scenario as a unifying explanation for both the high and dip states, and may signal an imminent nova eruption.
Read the full abstract

All authors Songpeng Pei, Xiaowan Zhang, Renzhi Su, Yongzhi Cai, Ziwei Ou, Qiang Li, Xiaoqin Ren, Taozhi Yang, Mingyue Li

High Energy Astrophysical Phenomena

Outburst Characteristics of Transient Low Mass X-ray Binary 4U 1608-52

Can Güngör

We present a deep study of the long-term X-ray light curve of 4U 1608-52 by investigating the fast rising exponential decay (FRED) outbursts, low intensity state (LIS) and quiescent intervals. By calibrating the onset times of the outbursts, we identify three distinct classes for the FRED-type events: (i) the long-high outbursts, exceeding ~50 d in duration with peak count rates above ~40 cnt/s; (ii) the short-medium outbursts, with durations of ~20 d and peak count rates of ~30-50 cnt/s; and (iii) the short-low outbursts, also lasting ~20 d but reaching only ~20-30 cnt/s at peak. We, furthermore, examine the relation between pre-outburst duration and the peak & integrated count rates of the upcoming outburst. We show that outbursts following longer quiescent periods tend to be more energetic.
Read the full abstract

Solar and Stellar Astrophysics

Enhanced Non-Thermal Line Broadening inside Coronal Cavities above Solar Prominences revealed by Spectral Imaging CoronaGraph

Chenxi Huangfu, Hui Fu, Bo Li et al. (+5 more)

Coronal cavities, often associated with prominences, are crucial structures in understanding coronal heating and the eruption mechanism of Coronal Mass Ejections (CMEs). Previous studies have identified their lower density, higher temperature, and flux rope structures. However, spectroscopic observations are still relatively scarce. In this study, we utilize the newly developed Spectral Imaging Coronagraph (SICG), Chinese H$\alpha$ Solar Explorer (CHASE), and AIA/SDO to analyze the morphology, temperature, Doppler shift, and non-thermal velocity of two coronal cavities observed on November 13, 2024. We find that coronal cavities are distinctly visible in SICG \ion{Fe}{14} 5303~Å\ and AIA 193~Å, whereas they are nearly absent in SICG \ion{Fe}{10} 6374~Å\ and AIA 171~Å. The spectroscopic measurements show that the two coronal cavities display asymmetric, ring-like structures in the \ion{Fe}{14} 5303~Å\ Doppler shift maps. The non-thermal velocities inside coronal cavities are significantly higher than those of the surrounding streamer areas. In addition, the core regions of coronal cavities, located directly above the prominences, exhibit the highest non-thermal velocities and Doppler velocities. Our results suggest the presence of waves and turbulence in coronal cavities, which are likely more intense than those in the adjacent streamer regions. We suggest that the interaction and exchange between the cold, dense prominence materials and the hot, low-density coronal materials are the main drivers of the waves and turbulence inside coronal cavities.
Read the full abstract

All authors Chenxi Huangfu, Hui Fu, Bo Li, ZhengHua Huang, MingZhe Sun, WeiXin Liu, XiaoYu Yu, LiDong Xia

High Energy Astrophysical Phenomena

The IXPE and multifrequency polarimetric view of the extreme blazars 1ES 1101-232 and RGB J0710+591

Fabrizio Tavecchio, Dawoon E. Kim, Gabriel Emery et al. (+53 more)

Multiwavelength polarimetry is a powerful tool to probe magnetic field and flow geometries in the relativistic jets of blazars. In this respect, particularly interesting are the sources whose synchrotron emission covers a broad range of frequencies, from radio to X-rays, such as the BL Lac objects of the HSP type. Previous measurements including radio, optical and X-ray data show a clear trend, with the degree of polarization increasing with frequency. Here we report radio, optical and X-ray observations ($Swift$, $Nustar$ and $IXPE$) of 1ES 1101-232 and RGB J0710+591, two blazars belonging to the puzzling subclass of extreme BL Lacs (EHBL). For 1ES 1101-232 we found a strong frequency-dependency of the degree of polarization (with a ratio $\Pi_X/\Pi_O\simeq 5.2$). For RGB J0710+591, IXPE derived a 1$\sigma$ upper limit $\Pi_X<11.6\%$, comparable with the measured optical degree of polarization (average $\Pi_O\sim 12\%$). We discuss the results in the framework of current interpretations and, in particular, we report an improved version of the stratified shock model that is able to reproduce the observed data of both sources.
Read the full abstract

All authors Fabrizio Tavecchio, Dawoon E. Kim, Gabriel Emery, Ioannis Liodakis, Iván Agudo, Paolo Coppi, Giampiero Tagliaferri, Laura Di Gesu, Tullia Sbarrato, Lucia Ballo, Alberto Sciaccaluga, Steven R. Ehlert, Giacomo Bonnoli, Francisco José Aceituno, Carolina Casadio, Víctor Casanova, Immacolata Donnarumma, Juan Escudero, Daniel Morcuende, Jorge Otero-Santos, Alfredo Sota, Vilppu Piirola, Pouya M. Kouch, Elina Lindfors, Kari Nilsson, Ioannis Myserlis, Mark Gurwell, Garrett Keating, Ramprasad Rao, Emmanouil Angelakis, Alexander Kraus, Ryo Imazawa, Mahito Sasada, Yasushi Fukazawa, Koji S. Kawabata, Makoto Uemura, Tsunefumi Mizuno, Tatsuya Nakaoka, Sumie Tochihara, Takahiro Akai, Hiroshi Akitaya, Rumen Bachev, Anton Strigachev, Petra Benke, Lena Debbrecht, Julia Eich, Florian Eppel, Andrea Gokus, Steven Hämmerich, Jonas Heßdörfer, Matthias Kadler, Sanghyun Kim, Dana Kirchner, Georgios Filippos Paraschos, Florian Rösch, Wladislaw Schulga

Cosmology and Nongalactic Astrophysics

Illuminating the Dark Sector: Understanding Modified Gravity Signatures with Cross-Correlations of Gravitational Waves and Large-Scale Structure

Chiara De Leo, Guadalupe Cañas-Herrera, Anna Balaudo et al. (+3 more)

We investigate the synergy between large-scale structure (LSS) observations and gravitational wave (GW) events for testing modified gravity. In particular, we forecast the LSS $\times$ GW cross-correlation signal using Stage-IV LSS surveys, such as Euclid, in combination with future detections from the Einstein Telescope. This cross-correlation provides a novel probe of fundamental physics, potentially revealing deviations from the $\Lambda$CDM paradigm that may not be accessible through electromagnetic observations alone. We describe the considered modified gravity scenarios, the relevant LSS and GW observables, and the synthetic forecast methodology. Our results demonstrate that combining LSS and GWs can significantly enhance constraints on departures from General Relativity, opening a new window for multi-messenger cosmology. We further assess the observational requirements GW experiments must meet to improve upon constraints obtainable from LSS alone.
Read the full abstract

All authors Chiara De Leo, Guadalupe Cañas-Herrera, Anna Balaudo, Matteo Martinelli, Alessandra Silvestri, Tessa Baker

Astrophysics of Galaxies

ALMA Observations of Cold Methanol Gas in the Large Magellanic Cloud (LMC): N79 South GMC

Suman Kumar Mondal, Takashi Shimonishi, Soumen Mondal et al. (+4 more)

We report ALMA continuum and molecular line observations at 0.1 pc resolution toward the super star cluster (SSC) candidate H72.97-69.39 in the N79 region of the LMC. The continuum emission has a sharp peak around the SSC candidate but is also widely distributed. We identify two continuum sources at the northern (N79S-1) and northwestern (N79S-2) positions of the SSC continuum peak, associated with CH$_3$OH emission. In addition to CH$_3$OH, we also detect H$_2$CO, H$_2$CS, CS, SO, CO, CN, and CCH at the positions of N79S-1 and N79S-2. The rotation diagram analysis of CH$_3$OH and SO lines yields an average gas temperature of 13 $\pm$ 0.4 K for N79S-1 and 15 $\pm$ 0.9 K for N79S-2. Most emission lines exhibit line widths of less than 2.8 km s$^{-1}$, consistent with emissions from cold, dense molecular cloud cores. The abundance of cold CH$_3$OH gas is estimated to be (2.1 $\pm$ 1.1)$\times$ 10$^{-9}$ at N79S-1 and (4.5 $\pm$2.5)$\times$ 10$^{-10}$ at N79S-2. Despite the lower metallicity in the LMC, the CH$_3$OH abundance at N79S-1 is comparable to that of similar cold sources in our Galaxy. However, the formation of organic molecules is inhibited throughout the N79 regions, as can be seen in the non-detection of CH$_3$OH in most of the regions. The two positions N79S-1 and N79S-2 would be exceptional positions, where CH$_3$OH production is efficient. The possible origins of cold CH$_3$OH gas in these dense cores are discussed, along with a possible explanation for the non-detection of CH$_3$OH in the SSC candidate.
Read the full abstract

All authors Suman Kumar Mondal, Takashi Shimonishi, Soumen Mondal, Prasanta Gorai, Kei E. I. Tanaka, Kenji Furuya, Ankan Das

Earth and Planetary Astrophysics

Raman Spectroscopy of Salt Deposits from the Simulated Subsurface Ocean of Enceladus

Jun Takeshita, Yuichiro Cho, Haruhisa Tabata et al. (+3 more)

Saturn's ice-covered moon Enceladus may host a subsurface ocean with biologically relevant chemistry. Plumes released from this ocean preserve information on its chemical state, and previous analyses suggest weakly to strongly alkaline pH (approximately pH 8–12). Constraining the pH requires identification of pH-sensitive minerals in plume deposits. Several analytical techniques could provide such mineralogical information, but few are practical for deployment on planetary missions. Raman spectrometers, which have recently advanced for in situ exploration and have been incorporated into flight instruments, offer a feasible approach for mineral identification on icy moons. However, their applicability to pH estimation from plume-derived minerals has not been investigated. In this study, we evaluate whether Raman measurements of plume particles deposited on the surface of Enceladus can be used to distinguish between weakly and strongly alkaline subsurface ocean models. Fluids with pH values of 9 and 11 were frozen under vacuum conditions analogous to those on Enceladus. The resulting salt deposits were then analyzed using a flight-like Raman spectrometer. The Raman spectra show pH-dependent carbonate precipitation: NaHCO$_3$ and Na$_2$CO$_3$ peaks were detected at pH 9, whereas only Na$_2$CO$_3$ peaks were detected at pH 11. These findings demonstrate that Raman spectroscopy can distinguish pH-dependent carbonate phases. This capability allows us to constrain whether the pH of the subsurface ocean is weakly alkaline or strongly alkaline, which is a key parameter for assessing its chemical evolution and potential habitability.
Read the full abstract

All authors Jun Takeshita, Yuichiro Cho, Haruhisa Tabata, Yoshio Takahashi, Daigo Shoji, Seiji Sugita

Cosmology and Nongalactic Astrophysics

Joint constraints on $R_h=ct$ cosmology from DESI DR2 BAO, CC, and SNIa Pantheon$^+$ sample

Amritansh Mehrotra, S. K. J. Pacif and A. F. Santos

We carry out a comparative analysis of the standard $\Lambda$CDM cosmological model and the alternative $R_h=ct$ framework using recent observational data from cosmic chronometers (CC), Type Ia supernova, and baryon acoustic oscillations. The study evaluates the ability of each model to reproduce the observed expansion history of the Universe through a joint statistical assessment based on $\chi^2$ statistics, Akaike Information Criterion $(AIC)$, Bayesian Information Criterion $(BIC)$, and Bayes factor. While both models yield acceptable fits, $\Lambda$CDM consistently attains lower information-criterion values and higher likelihood, indicating a superior overall performance. An examination of the redshift evolution of the Hubble parameter $H(z)$ and the deceleration parameter $q(z)$ shows that $\Lambda$CDM naturally captures the transition from early-time deceleration to late-time acceleration, where as $R_h=ct$ predicts a strictly linear expansion. We also estimate the age of the Universe within both models, obtaining $t_0^{\Lambda CDM}= 13.676_{-0.81}^{+0.92}$Gyr and $t_0^{R_h=ct}= 16.035_{-0.98}^{+1.09}$Gyr. The posterior-derived age in the $\Lambda$CDM framework is broadly consistent with the Planck 2018 CMB result. This agreement is interpreted as a validation of the analysis pipeline and the reliability of the DESI DR2, CC, and supernova constraints, rather than as a new result for $\Lambda$CDM, and serves as a benchmark for assessing the viability of the $R_h=ct$ model. Recent JWST observations of unexpectedly mature high-redshift galaxies have renewed discussion regarding the timeline of early structure formation; although these results remain under active investigation, they underscore that fully resolving cosmic evolution may require refinements beyond the concordance paradigm.
Read the full abstract

Solar and Stellar Astrophysics

Height and Energy Evolution of X-ray Double Sources in a Solar Flare

Hanya Pan, Astrid M. Veronig and Rui Liu

In the standard model, magnetic reconnection at a vertical current sheet above the flare arcade is key to explaining many aspects of solar eruptions. The supra-arcade region is where the vertical current sheet is supposedly located, and X-ray/EUV emission therein reflects underlying energy release and transport processes, therefore providing valuable insight into the structure and evolution of the current sheet. Previous studies have focused primarily on the impulsive phase of flares, but phenomena in the decay phase are also crucial for understanding the complete flaring scenario. In this paper, we investigated an M6.7-class limb flare that occurred on August 28, 2022, combining observations from the Solar Orbiter (SolO) and Solar Dynamics Observatory (SDO). Coronal X-ray sources are continually observed by the Spectrometer/Telescope for Imaging X-rays (STIX) onboard SolO for over two hours, revealing a multi-phase evolution with varying velocities and multiple substructures, with higher-energy components consistently appearing at higher altitudes. Such a height-energy relation is notably observed in a double coronal source during the decay-phase, which is dominated by thermal emission. The energy distribution of the double source distinguish itself from previous studies that showed a symmetric distribution, with the higher-energy components being closer to the center of the double source during the impulsive phase. Obtained from two opposite side-on perspectives on the supra-arcade region, these findings reveal the spatio-temporal complexity of the energy release process in the post-flare current sheet during the decay phase.
Read the full abstract

Astrophysics of Galaxies

How significant is the lensing interpretation of GW231123?

Xikai Shan, Huan Yang and Shude Mao

GW231123 is one of the most unusual gravitational-wave (GW) events, with exceptionally large inferred masses and near-extremal spins, offering an opportunity to test whether propagation effects contribute to these properties. We therefore examine whether the data support wave-optics microlensing embedded in a strong-lensing galaxy, whose detection becomes increasingly likely as observations accumulate, whether this interpretation can explain these properties, and how significant the preference remains under detector noise and waveform systematics. We compare six hypotheses: unlensed, isolated point mass, and embedded point-mass (EPM) and binary-lens (EB) effective models in Type-I (minimum) and Type-II (saddle) macro images. The EB Type-I model is most favored. For the most accurate waveform model NRSur7dq4, it gives $\log_{10}B^{\rm EB-I}_{\rm U}=2.60$, versus $0.89$ for Type II, indicating sensitivity to macro-image geometry. Within Type I, however, the binary improves over the point mass by only $\log_{10}B^{\rm EB-I}_{\rm EPM-I}=0.16$ and $\Delta\ln\mathcal{L}_{\max}=0.56$, providing no clear evidence for structure beyond a single effective perturber. Moreover, under embedded lensing, waveform-template discrepancies and inferred masses and spins are reduced. However, real O4a backgrounds from numerical-relativity injections show that the apparent lensing evidence is sensitive to waveform systematics and realistic detector noise: although the commonly used waveform IMRPhenomXPHM gives the largest Bayes factor, $\log_{10}B^{\rm EB-I}_{\rm U}=4.52$, it is less exceptional relative to its own background, with a false-alarm probability of $6.5$–$8\%$, whereas NRSur7dq4 gives only $2$–$3\%$. Thus, waveform systematics can amplify apparent lensing evidence, but GW231123 remains an intriguing lensing candidate.
Read the full abstract

Instrumentation and Methods for Astrophysics

The Simons Observatory: Detector Polarization Angle Calibration using Sparse Wire Grid with Initial Data Sets of the Small Aperture Telescope

Hironobu Nakata, Shunsuke Adachi, Kyohei Yamada et al. (+22 more)

Improved measurements of $B$-modes in the cosmic microwave background can be obtained through accurate calibration of the orientation of detector antennas as projected onto the sky. Miscalibration of the detector polarization angle leads to a leakage of $E$-modes into $B$-modes, which can bias the detection of the latter. To achieve a $\sigma(r)$ of 0.003, the Simons Observatory Small Aperture Telescopes are required to calibrate the global polarization angle on the sky with an accuracy ${\lesssim}0.1^\circ$. We demonstrate a fully remote-controllable calibration system using a “sparse wire grid," which injects a rotatable linear polarized signal across the telescope's focal plane. This calibration system is installed and operational on a Small Aperture Telescope at its observing site at the Parque Astronómico in the Atacama desert in Chile. We developed a pipeline for the detector polarization angle calibration, and demonstrate it using initial data for 93~GHz and 145~GHz frequency bands. The observed distribution of detector polarization angles is in agreement with the instrument design. Statistical uncertainties for the relatively calibrated polarization angles are $0.02^\circ$ and $0.03^\circ$ at 93~GHz and 145~GHz, respectively. Systematic uncertainty was evaluated to be $0.08^\circ$ at the hardware development and fabrication stage. Their sum in quadrature is less than $0.1^\circ$.
Read the full abstract

All authors Hironobu Nakata, Shunsuke Adachi, Kyohei Yamada, Michael Randall, Yutaro Kasai, Kam Arnold, Bryce Bixler, Yuji Chinone, Kevin T. Crowley, Nadia Dachlythra, Samuel Day-Weiss, Nicholas Galitzki, Serena Giardiello, Bradley R. Johnson, Brian Keating, Brian J. Koopman, Akito Kusaka, Jack Lashner, Federico Nati, Lyman Page, Daichi Sasaki, Yoshinori Sueno, Junya Suzuki, Osamu Tajima, Tran Tsan

High Energy Astrophysical Phenomena

Physical Conditions for Synthesis of Sc, Ti, and V in Neutrino-driven Supernovae

Ryota Hatami, Nozomu Tominaga, Takashi Yoshida et al. (+2 more)

We present the results of simulations of nucleosynthesis in a core-collapse supernova (CCSN) including the neutrino process. Using the Si layer of $13M_\odot$ zero-metal progenitor as the initial composition, we calculate the nucleosynthesis by adopting the temperature, density, neutrino flux, and duration of nucleosynthesis as arbitrary parameters and compare the results with the observed abundances ratio of Sc, Ti, and V in very metal-poor (VMP) stars taken from the Stellar Abundances for Galactic Archaeology (SAGA) database. As a result, for the first time, we identify the quantitative requirements on local physical conditions. To reproduce the abundances ratios in the VMP stars, the explosive nucleosynthesis should take place under the neutrino exposure, which is time integration of neutrino flux, of $\sigma_\nu\sim 10^{35}\,\mathrm{erg~cm^{-2}}$ and temperature of $2.0\,\mathrm{GK}\leq T \leq 3.2\,\mathrm{GK}$. The dependence on the density and each value of the neutrino flux and the duration of nucleosynthesis is weak. We also discuss whether the quantitative requirements are realized during the explosion. Although the requirements are difficult to be realized in the one-dimensional simulations, the non-monotonic thermal evolution shown in recent three-dimensional simulations may satisfy them. Because the evolution is likely caused by turbulent motion stemming from the initial asphericity of the progenitor, it is important to calculate the long-term three-dimensional supernova explosion of multi-dimensional metal-free progenitor models and follow the nucleosynthesis self-consistently.
Read the full abstract

All authors Ryota Hatami, Nozomu Tominaga, Takashi Yoshida, Hideyuki Umeda, Tomoya Takiwaki

Cosmology and Nongalactic Astrophysics · Cross-listed from gr-qc

The First Model-Independent Upper Bound on Micro-lensing Signature of the Highest Mass Binary Black Hole Event GW231123

Aniruddha Chakraborty and Suvodip Mukherjee

The recently discovered gravitational wave event, GW231123, is the most massive binary black hole merger detected to date. The inferred source masses of the event fall within the pair-instability supernova mass gap, where black holes formed directly from stellar progenitors are expected to be rare, making alternative formation scenarios for such massive black holes especially relevant. One proposed explanation is gravitational lensing, which can make the source masses to be inferred as higher than their true values. In this work, we search for lensing signatures in GW231123, together with other O4a events, using a model-independent approach with mu-GLANCE. The method tests residual strain for correlated features across the detector network via cross-correlation and infers lensing-induced modulations within a Bayesian framework. Our analysis finds no strong evidence for lensing in GW231123, but reveals a potential residual feature that could be consistent with microlensing, with a modulation amplitude of up to 0.8 at 95% confidence. However, we find that waveform systematics for such heavy binary systems are sufficiently large to shadow the lensing signatures in short-duration signals like GW231123, preventing any definitive claim of lensing at this stage. We conclude that, if this event is lensed, similar lensed events will be detectable in the near future with current detector sensitivity, opening a new discovery space for lensed gravitational waves with the aid of more accurate waveform models.
Read the full abstract

Astrophysics of Galaxies

The Milky Way Bulge Extra-Tidal Star Survey: NGC 6569

Joanne Hughes, Andrea Kunder, Kevin Covey et al. (+25 more)

We present spectroscopic evidence for tidal debris associated with the bulge globular cluster NGC 6569, based on medium-resolution (R ~ 11,000) Anglo-Australian Telescope spectra of 303 stars. Targets were selected using Blanco DECam Bulge Survey (BDBS) photometry and Gaia DR3 astrometry, spanning 7-30 arcmin (~1-5 rt, where rt is the King-model tidal radius) from the cluster center. Orbit-based modeling predicts a strongly time-variable Jacobi radius, with rJ ~ 8-11 arcmin near pericenter and ~18-22 arcmin near apocenter, so stars just outside rt can be unbound and feeding leading and lagging tidal tails. We identify 40 stars with kinematics and abundances consistent with previous, or borderline, cluster membership. The seven highest-quality candidates (S/N > 30) have mean [Fe/H] = -0.83 +/- 0.14 and [alpha/Fe] = +0.38 +/- 0.06 dex, matching the bound population. Interpreting these stars as recently stripped debris implies a present-day mass-loss rate of 1.0-1.6 solar masses per Myr, or 5.6 +/- 1.3% of the current cluster mass per Gyr. These results indicate ongoing tidal stripping of NGC 6569 and quantify its contribution to the bulge field. This paper is part of the Milky Way Bulge Extra-Tidal Star Survey (MWBest) and is our first detailed debris study of a massive bulge globular cluster.
Read the full abstract

All authors Joanne Hughes, Andrea Kunder, Kevin Covey, Kathryn Devine, Kristen A. Larson, Carlos Campos, Adrian M. Price-Whelan, Joseph E. McEwen, Gabriel I. Perren, Christian I. Johnson, Craig Horton, Luke Smith, Sarah Torset, Cynthia Luna, Matthew Kolmanovsky, Fiona Kovisto, Leander Villarta, Vy Vuong, Iulia T. Simion, Kyle Webster, Erika Silva, Catherine A. Pilachowski, R. Michael Rich, Justin A. Kader, Andreas J. Koch-Hansen, Meridith Joyce, Sean McAdam, Faith Benda

High Energy Astrophysical Phenomena

Pulsar electrodynamics inferred from frequency-dependent circular polarization diversity

Shunshun Cao, Yanjun Guo, Jinchen Jiang et al. (+3 more)

The nature of coherent radio emission is still challenging even after more than half a century of pulsar discovery, but it is generally a consensus that single-pulse observations are essential for probing the magnetospheric dynamics, especially with the largest single-dish telescope FAST (Five-hundred-meter Aperture Spherical radio Telescope). This paper aims to explain the observed diversity of single pulse circular polarization, and to constrain the multiplicity and Lorentz factor of pulsar magnetospheric plasma, with the mode coupling model in the limiting polarization region. Assuming that circular polarization comes only from wave mode coupling, we apply a Bayesian analysis to the FAST observed single pulse circular polarization spectra, involving numerical solving of wave mode coupling equations, and analyze the posterior probability distribution functions of the parameters. Although the model fails to quantitatively fit most circular polarization spectra, circular polarization of different frequency evolution is reproduced. For three chosen pulsars, the Bayesian analysis constrains the multiplicity to be approximately $10^{0}\sim10^{2}$, and the Lorentz factor to be approximately $10^{0.5}\sim10^{2}$. Pulsar circular polarization could be induced by wave mode coupling. The plasma flow responsible for coherent radio emission carries only a very small fraction of the pulsar spin-down energy loss.
Read the full abstract

All authors Shunshun Cao, Yanjun Guo, Jinchen Jiang, Kejia Lee, Weiyang Wang, Renxin Xu

Astrophysics of Galaxies · Cross-listed from gr-qc

Bose-Einstein Condensate dark matter with logarithmic nonlinearity

Zahra Haghani and Tiberiu Harko

If dark matter is composed of massive bosons, a Bose-Einstein Condensation process must have occurred during the cosmological evolution. Therefore, galactic dark matter may be in a form of a self-gravitating condensate, in the presence of self-interactions. We consider the possibility that the self-interacting potential of the condensate dark matter is of the logarithmic form. In order to describe the condensate dark matter we use the Gross-Pitaevskii equation with a logarithmic nonlinearity, and the Thomas-Fermi approximation. With the use of the hydrodynamic representation of the Gross-Pitaevskii equation we obtain the equation of state of the condensate, which has the form of the ideal gas equation of state, with the pressure proportional to the dark matter density. The basic equation describing the density distribution of the static condensate is derived, and its solution is obtained in the form of a series solution, constructed with the help of the Adomian Decomposition Method. To test the model we consider the properties of the galactic rotation curves in the logarithmic Bose-Einstein Condensate dark matter scenario, by using a sample from the Spitzer Photometry and Accurate Rotation Curves (SPARC) data. The fit of the theoretical predictions of the rotation curves with the observational data indicate that the logarithmic Bose-Einstein Condensate dark matter model gives an acceptable description of the SPARC data, and thus it may be considered as a possible candidate for the in depth understanding of the dark matter properties.
Read the full abstract

Cosmology and Nongalactic Astrophysics · Cross-listed from hep-ph

Gravitational Production of Massive Spin-2 Particles During Reheating

Sarunas Verner

We study the minimal gravitational portal for a massive spin-2 dark matter candidate $X_{\mu\nu}$ produced during perturbative reheating. The dark sector couples to the visible sector only via gravity, and we analyze two unavoidable channels: (i) inflaton condensate annihilation, $\phi+\phi \to X+X$, and (ii) thermal scatterings, ${\rm SM}+{\rm SM}\to X+X$, both mediated by graviton exchange. Working in the Fierz-Pauli framework for a free massive spin-2 field of mass $m_2$, we derive the graviton-mediated amplitudes and perform a full helicity decomposition of the final state. The relic abundance is obtained analytically in terms of $m_2$ and the reheating temperature $T_{\rm RH}$. In the light mass regime $m_2 \ll m_\phi$ (with $m_\phi$ the inflaton mass during oscillations), production is overwhelmingly dominated by the longitudinal (helicity-0) mode: the $2\to2$ cross section is parametrically enhanced, scaling as $\sim (m_\phi/m_2)^4$, and yields efficient dark matter production despite purely gravitational couplings. Compared to lower-spin cases (spin-$0$, $1/2$, $1$, and $3/2$), massive spin-$2$ production is substantially more efficient for the same reheating history. Over most of the parameter space the inflaton condensate channel dominates the yield, while the thermal contribution is negligible. Avoiding overproduction typically requires either a relatively low $T_{\rm RH}$ or a spin-$2$ mass near threshold, $m_2 \lesssim m_\phi$. This places the spin-$2$ portal on similar footing to other higher spins in reheating scenarios, while emphasizing the central role of the helicity-$0$ mode and the reheating history in setting the dark matter density.
Read the full abstract

Cosmology and Nongalactic Astrophysics

$\mathbf{\Omega_1\Omega_2}$-$\mathbf{\Lambda}$CDM: A promising phenomenological extension of the standard model of cosmology

Suresh Kumar

We investigate a phenomenological extension of the standard $\Lambda$CDM framework, the $\Omega_1\Omega_2$-$\Lambda$CDM model, in which the total energy density of the universe is expanded in powers of $1+z$. This parameterization recovers $\Lambda$CDM and introduces two additional terms, $\Omega_1(1+z)$ and $\Omega_2(1+z)^2$, in the dark energy sector alongside the cosmological constant, leading to a physically interpretable and observationally testable effective dark energy dynamics. Using Planck cosmic microwave background (CMB) data, we find that the model allows additional freedom in the late-time expansion history while preserving standard early-universe physics. When DESI baryon acoustic oscillation (BAO) data are included, the inferred Hubble constant is $H_0 = 69.74 \pm 0.77~\mathrm{km\;s^{-1}\;Mpc^{-1}}$ (68% CL), consistent with Tip of the Red Giant Branch (TRGB) measurements from the Carnegie–Chicago Hubble Program (CCHP). The reconstructed dark energy equation of state exhibits a smooth transition across the phantom divide followed by asymptotic de Sitter behavior, modifying late-time dynamics while maintaining standard early-time cosmology. Overall, controlled late-time deviations from $\Lambda$CDM improve cosmological concordance.
Read the full abstract

Astrophysics of Galaxies

Fragmenting Filaments and Evolving Cores – Insights from Dust Polarisation Study of a filament in Northern Orion B

Kshitiz K. Mallick, Doris Arzoumanian, Satoko Takahashi et al. (+5 more)

We present an analysis of polarised dust emission at 850 micron for a parsec long filament in the northern part of the Orion B molecular cloud. The region was observed by the JCMT SCUBA-2/POL-2 polarimeter. The filament has a line mass (~80 Msun/pc) larger than the critical (magnetic) line mass (~37 Msun/pc); and hosts one starless, three prestellar, and four protostellar cores, with masses in the range 0.13 to 9.13 Msun. The mean (debiased) polarisation fraction of the filament and core pixels was calculated to be 5.3+/-0.3% and 3.2+/-0.3%, respectively, likely reflecting their distinct physical conditions. The polarisation fraction for the cores does not depend on the type of core, and was found to decrease with increasing column density, varying from 6-11% at the filament edges to 1$^{+0.7}_{-0.1}$% in the denser parts ($N_{H2}\gtrsim$2x10$^{22}$cm$^{-2}$). Magnetic field orientation of the protostellar cores, in contrast to prestellar cores, appears to be relatively aligned with the magnetic field orientation of the local filament in this region. Using the Davis-Chandrasekhar-Fermi formalism the plane-of-sky magnetic field strength for the protostellar cores (~39-110 microG) was found to be higher than that of the prestellar cores (~22-61 microG); and weakest for the starless core (~6 microG). The average value for the filament was found to be ~31 microG. The magnetic field-volume density relation for the prestellar/starless cores and protostellar cores suggests a transition from weak field case to strong field case as the cores evolve from prestellar to protostellar phase.
Read the full abstract

All authors Kshitiz K. Mallick, Doris Arzoumanian, Satoko Takahashi, Ray S. Furuya, Yoshiaki Misugi, Yoshito Shimajiri, Kate Pattle, Shu-ichiro Inutsuka

Cosmology and Nongalactic Astrophysics · Cross-listed from hep-ph

Scalar-Mediated Inelastic Dark Matter as a Solution to Small-Scale Structure Anomalies

Zihan Wang

We propose a scalar-mediated Self-Interacting Dark Matter (SIDM) model to address small-scale structure anomalies such as the core-cusp and diversity problems. The model is composed by a leptophilic scalar mediator and a pseudo-Dirac dark matter candidate with a mass splitting of 100ev.We imposed a dark discrete $\mathbb{Z}_2$ symmetry forbids tree-level elastic scattering. Therefore creates kinematic threshold that suppresses scattering in ultra-faint satellite galaxies while enabling large self-interaction cross-sections in dwarf galaxies via resonant enhancement. To satisfy Big Bang Nucleosynthesis (BBN) requirements, we introduce a dimension-5 magnetic dipole operator that enable the decay of the excited state ($\chi_2 \rightarrow \chi_1 \gamma$). This operator also provides a unique, low-threshold signal for direct detection experiments, characterized by a distinct $1/E_R$ recoil spectrum. We identify a benchmark parameter space around ($m_\chi \approx 40$ GeV, $m_\phi \approx 20$ MeV) where non-perturbative coupled-channel dynamics successfully reconcile astrophysical observations with cosmological bounds, including CMB constraints on annihilation.
Read the full abstract

Astrophysics of Galaxies

Validating the CROCODILE model within the AGORA galaxy simulation framework

Pablo Granizo, Yuri Oku and Kentaro Nagamine

Numerical galaxy formation simulations are sensitive to numerical methods and sub-grid physics models, making code comparison projects essential for quantifying uncertainties. Here, we evaluate GADGET4-OSAKA within the AGORA project framework by conducting a systematic comparison with its predecessor. We perform an isolated disk galaxy and a cosmological zoom-in run of a Milky Way-mass halo, following the multi-step AGORA calibration procedure. By systematically deconstructing the updated stellar feedback model, we demonstrate that mechanical momentum injection is necessary to suppress unphysical gas fragmentation and regulate star formation, yielding agreement with the Kennicutt-Schmidt relation. Meanwhile, stochastic thermal heating is essential for driving a hot, metal-enriched gaseous halo, thereby creating a multiphase circumgalactic medium that is absent in the predecessor code. In the cosmological context, we calibrate the simulation to match the stellar mass growth history targeted by the AGORA collaboration. The validated GADGET4-OSAKA simulation has been contributed to the AGORA CosmoRun suite, providing a new data point for understanding the impact of numerical and physical modeling choices on galaxy evolution.
Read the full abstract

Cosmology and Nongalactic Astrophysics

Weak Lensing Mass Calibration of the ACT DR5 Galaxy Clusters with the DES Year 3 Weak Lensing Data

T. Shin, E. J. Baxter, E. Lee et al. (+93 more)

We use weak gravitational lensing measurements from Year 3 Dark Energy Survey data to calibrate the masses of 443 galaxy clusters selected via the Sunyaev-Zel'dovich effect from Atacama Cosmology Telescope Data Release 5 maps. We incorporate redshift and SZ measurements for individual clusters into a hierarchical model for the stacked lensing signals and perform Bayesian analyses to constrain hydrostatic mass bias of the clusters. Our treatment of systematic uncertainties includes a prescription for measuring and accounting for the weak lensing boost factor, consideration of a miscentering effect, as well as marginalization over uncertainties in the source galaxy photometric redshift distributions and shear calibration. The constraints on the normalization of the mass-observable relation have a precision of 7%, with the mean WL halo mass $M_{\rm 500c} = 5.4 \times 10^{14} M_{\odot}$. We measure the bias between the true cluster mass and the mass estimated from the SZ signal assuming hydrostatic equilibrium, to be $1-b = 0.74^{+0.06}{-0.05}$ over the full sample. When splitting the clusters into high and low redshift bins, we measure $1-b = 0.58^{+0.06}{-0.05}$ and $0.81^{+0.08}{-0.06}$, respectively. When introducing additional freedom in redshift and mass to the hydrostatic bias model, we find that $1-b$ decreases with redshift (with the power law of $-1.8^{+0.5}{-0.6}$, 99.95% confidence), consistent with findings from other recent studies, while we do not find any significant trend in mass. We also demonstrate that our result is robust against various systematics such as a scale cut, priors on baryonic and miscentering parameters, and degree of scatter in mass-observable relation. The weak-lensing mass calibration presented in this study will be a useful tool for using the ACT clusters as probes of astrophysics, and as a step towards using their abundance as a cosmological probe.
Read the full abstract

All authors T. Shin, E. J. Baxter, E. Lee, N. Battaglia, A. Alarcon, A. Amon, M. Becker, G. Bernstein, J. R. Bond, A. Campos, C. Chang, R. Chen, A. Choi, J. DeRose, S. Dodelson, C. Doux, J. Dunkley, J. Elvin-Poole, J. H. Esteves, S. Everett, A. Ferté, M. Gatti, S. Grandis, D. Gruen, I. Harrison, J. C. Hill, M. Hilton, M. Jarvis, N. MacCrann, J. McCullough, K. Moodley, T. Mroczkowski, J. Myles, A. Navarro Alsina, A. Nicola, L. Page, S. Pandey, J. Prat, M. Raveri, B. Ried Guachalla, R. P. Rollins, C. Sanchez, L. F. Secco, E. Sheldon, C. Sifón, M. Troxel, I. Tutusaus, A. von der Linden, E. Wollack, B. Yin, M. Aguena, S. S. Allam, O. Alves, F. Andrade-Oliveira, D. Bacon, S. Bocquet, D. Brooks, R. Camilleri, A. Carnero Rosell, J. Carretero, F. J. Castander, M. Costanzi, L. da Costa, M. E. da Silva Pereira, T. Davis, J. De Vicente, S. Desai, B. Flaugher, J. Frieman, J. Garcia-Bellido, G. Gutierrez, S. Hinton, D. L. Hollowood, D. Huterer, D. James, S. Lee, J. Marshall, J. Mena-Fernández, F. Menanteau, R. Miquel, J. Mohr, J. Muir, R. Ogando, A. Plazas Malagón, A. Porredon, K. Romer, E. Sanchez, D. Sanchez Cid, I. Sevilla, M. Smith, M. Soares-Santos, E. Suchyta, M. Swanson, C. To, N. Weaverdyck, J. Weller

Sunday 21 December

Instrumentation and Methods for Astrophysics

Optical SETI at ESO in the 2040s

Valenitn D. Ivanov

The searches for other life and for intelligence are fundamental problems that science faces today. Most searches so far have been focused on radio, but optical laser communication is an alternative, well suited for a ground-based observatory. A project to search for artificial laser communications with the current and future extreme multiplexity spectroscopic facilities that ESO may develop by the 2040s is outlined. The monochromatic light is a clearly identifiable technosignature. The enormous corollary outreach potential of this initiative is underlined.
Read the full abstract

Instrumentation and Methods for Astrophysics

EuroHPC SPACE CoE: Redesigning Scalable Parallel Astrophysical Codes for Exascale

Nitin Shukla, Alessandro Romeo, Caterina Caravita et al. (+36 more)

High Performance Computing (HPC) based simulations are crucial in Astrophysics and Cosmology (A&C), helping scientists investigate and understand complex astrophysical phenomena. Taking advantage of exascale computing capabilities is essential for these efforts. However, the unprecedented architectural complexity of exascale systems impacts legacy codes. The SPACE Centre of Excellence (CoE) aims to re-engineer key astrophysical codes to tackle new computational challenges by adopting innovative programming paradigms and software (SW) solutions. SPACE brings together scientists, code developers, HPC experts, hardware (HW) manufacturers, and SW developers. This collaboration enhances exascale A&C applications, promoting the use of exascale and post-exascale computing capabilities. Additionally, SPACE addresses high-performance data analysis for the massive data outputs from exascale simulations and modern observations, using machine learning (ML) and visualisation tools. The project facilitates application deployment across platforms by focusing on code repositories and data sharing, integrating European astrophysical communities around exascale computing with standardised SW and data protocols.
Read the full abstract

All authors Nitin Shukla, Alessandro Romeo, Caterina Caravita, Lubomir Riha, Ondrej Vysocky, Petr Strakos, Milan Jaros, João Barbosa, Radim Vavrik, Andrea Mignone, Marco Rossazza, Stefano Truzzi, Vittoria Berta, Iacopo Colonnelli, Doriana Medić, Elisabetta Boella, Daniele Gregori, Eva Sciacca, Luca Tornatore, Giuliano Taffoni, Pranab J. Deka, Fabio Bacchini, Rostislav-Paul Wilhelm, Georgios Doulis, Khalil Pierre, Luciano Rezzolla, Tine Colman, Benoît Commerçon, Othman Bouizi, Matthieu Kuhn, Erwan Raffin, Marc Sergent, Robert Wissing, Guillermo Marin, Klaus Dolag, Geray S. Karademir, Gino Perna, Marisa Zanotti, Sebastian Trujillo-Gomez

Cosmology and Nongalactic Astrophysics

Constraints on the polarization angle oscillations of the Crab Nebula with the Simons Array and its applications to the search for axion-like particles

Tylor Adkins, Shahed Shayan Arani, Kam Arnold et al. (+27 more)

We present a search for polarization oscillation of the Crab Nebula, also known as Tau A, at millimeter wavelengths using observations with the Simons Array, the successor experiment to POLARBEAR. We follow up on previous work by POLARBEAR using 90 GHz band data of the 2023 observing season of the Simons Array to evaluate the variability of Tau A's polarization angle. Tau A is widely used as a polarization angle calibration source in millimeter-wave astronomy, and thus it is necessary to validate the stability. Additionally, an interesting application of the time-resolved polarimetry of Tau A is to search for axion-like particles (ALPs). We do not detect a global signal across the frequencies considered in this analysis and place a median 95% upper bound of polarization oscillation amplitude $A<0.12^{\circ}$ over oscillation frequencies from 3.39 year$^{-1}$ to 1.50 day$^{-1}$. This constrains the ALP-photon coupling at a median 95% upper bound of $g_{a\gamma\gamma}< 3.84\times 10^{-12}\times\left(m_a/10^{-21}\,\mathrm{eV}\right)$ in the mass range from $4.4\times10^{-22}$ to $7.2\times10^{-20}$ eV, assuming the ALP constitutes all of dark matter, its field is a stochastic Gaussian field, and it is the sole source of Tau A's polarization angle oscillation. Additionally, we do not detect signal at the frequencies where 2.5$\sigma$ hints were previously reported by POLARBEAR, but we do not exclude these signals at the 95% confidence level.
Read the full abstract

All authors Tylor Adkins, Shahed Shayan Arani, Kam Arnold, Carlo Baccigalupi, Darcy R. Barron, Bryce Bixler, Yuji Chinone, Matthew R. Chu, Kevin T. Crowley, Nicole Farias, Takuro Fujino, Masaya Hasegawa, Masashi Hazumi, Haruaki Hirose, Jennifer Ito, Oliver Jeong, Daisuke Kaneko, Brian Keating, Akito Kusaka, Adrian T. Lee, Masaaki Murata, Lucio Piccirillo, Christian L. Reichardt, Kana Sakaguri, Praween Siritanasak, Satoru Takakura, Sayuri Takatori, Osamu Tajima, Kyohei Yamada, Yuyang Zhou