bluuebunny/crossref_metadata_2025_split huggingface dataset:
Impact of systematic redshift errors on the cross-correlation of the Lyman-α forest with quasars at small scales using DESI Early Data
Authors: Bault Abby , Kirkby David , Guy Julien , Brodzeller Allyson , Aguilar J. , Ahlen S. , Bailey S. , Brooks D. , Cabayol-Garcia L. , Chaves-Montero J. , Claybaugh T. , Cuceu A. , Dawson K. , de la Cruz R. , de la Macorra A. , Dey A. , Doel P. , Filbert S. , Font-Ribera A. , Forero-Romero J.E. , Gaztañaga E. , Gontcho S.Gontcho A. , Gordon C. , Herrera-Alcantar H.K. , Honscheid K. , Iršič V. , Karaçaylı N.G. , Kehoe R. , Kisner T. , Kremin A. , Lambert A. , Landriau M. , Le Guillou L. , Levi M.E. , Manera M. , Martini P. , Meisner A. , Miquel R. , Montero-Camacho P. , Moustakas J. , Muñoz-Gutiérrez A. , Nie J. , Niz G. , Palanque-Delabrouille N. , Percival W.J. , Pérez-Ràfols I. , Poppett C. , Prada F. , Ramírez-Pérez C. , Ravoux C. , Rezaie M. , Rossi G. , Sanchez E. , Schlafly E.F. , Schlegel D. , Schubnell M. , Silber J. , Tan T. , Tarlé G. , Walther M. , Weaver B.A. , Zhou Z. 
Published: January 2025

Abstract
The Dark Energy Spectroscopic Instrument (DESI) will measure millions of quasar spectra by the end of its 5 year survey. Quasar redshift errors impact the shape of the Lyman-α forest correlation functions, which can affect cosmological analyses and therefore cosmological interpretations. Using data from the DESI Early Data Release and the first two months of the main survey, we measure the systematic redshift error from an offset in the cross-correlation of the Lyman-α forest with quasars. We find evidence for a redshift dependent bias causing redshifts to be underestimated with increasing redshift, stemming from improper modeling of the Lyman-α optical depth in the templates used for redshift estimation. New templates were derived for the DESI Year 1 quasar sample at z > 1.6 and we found the redshift dependent bias, Δr
∥, increased from -1.94 ± 0.15 h
-1 Mpc to -0.08 ± 0.04 h
-1 Mpc (-205 ± 15 km s-1 to -9.0 ± 4.0 km s-1). These new templates will be used to provide redshifts for the DESI Year 1 quasar sample.
Suppressing the sample variance of DESI-like galaxy clustering with fast simulations
Authors: Ding Z. , Variu A. , Alam S. , Yu Y. , Chuang C. , Paillas E. , Garcia-Quintero C. , Chen X. , Mena-Fernández J. , Aguilar J. , Ahlen S. , Brooks D. , Claybaugh T. , de la Macorra A. , Doel P. , Fanning K. , Forero-Romero J.E. , Gaztañaga E. , Gontcho S.Gontcho A. , Gutierrez G. , Hahn C. , Honscheid K. , Howlett C. , Juneau S. , Kehoe R. , Kisner T. , Kremin A. , Lambert A. , Landriau M. , Le Guillou L. , Manera M. , Miquel R. , Mueller E. , Myers A.D. , Nie J. , Niz G. , Poppett C. , Rezaie M. , Rossi G. , Sanchez E. , Schubnell M. , Seo H. , Silber J. , Sprayberry D. , Tarlé G. , Vargas-Magaña M. , Zou H. 
Published: January 2025

Abstract
Ongoing and upcoming galaxy redshift surveys, such as the Dark Energy Spectroscopic Instrument (DESI) survey, will observe vast regions of sky and a wide range of redshifts. In order to model the observations and address various systematic uncertainties, N-body simulations are routinely adopted, however, the number of large simulations with sufficiently high mass resolution is usually limited by available computing time. Therefore, achieving a simulation volume with the effective statistical errors significantly smaller than those of the observations becomes prohibitively expensive. In this study, we apply the Convergence Acceleration by Regression and Pooling (CARPool) method to mitigate the sample variance of the DESI-like galaxy clustering in the AbacusSummit simulations, with the assistance of the quasi-N-body simulations FastPM.
Based on the halo occupation distribution (HOD) models, we construct different FastPM galaxy catalogs, including the luminous red galaxies (LRGs), emission line galaxies (ELGs), and quasars, with their number densities and two-point clustering statistics well matched to those of AbacusSummit.
We also employ the same initial conditions between AbacusSummit and FastPM to achieve high cross-correlation, as it is useful in effectively suppressing the variance.
Our method of reducing noise in clustering is equivalent to performing a simulation with volume larger by a factor of 5 and 4 for LRGs and ELGs, respectively.
We also mitigate the standard deviation of the LRG bispectrum with the triangular configurations k
2 = 2k
1 = 0.2 h Mpc-1 by a factor of 1.6.
With smaller sample variance on galaxy clustering, we are able to constrain the
baryon acoustic oscillations (BAO)
scale parameters to higher precision. The CARPool method will be beneficial to better constrain the theoretical systematics of BAO, redshift space distortions (RSD) and primordial
non-Gaussianity (NG).
Impact and mitigation of spectroscopic systematics on DESI DR1 clustering measurements
Authors: Krolewski A. , Yu J. , Ross A.J. , Penmetsa S. , Percival W.J. , Zhou R. , Wilson M.J. , Hou J. , Aguilar J. , Ahlen S. , Brooks D. , Chaussidon E. , Claybaugh T. , de la Macorra A. , Dey Biprateep , Forero-Romero J.E. , Gontcho S.Gontcho A. , Guy J. , Honscheid K. , Juneau S. , Kirkby D. , Kisner T. , Kremin A. , Lambert A. , Le Guillou L. , Levi M.E. , Martini P. , Meisner A. , Miquel R. , Moustakas J. , Myers A.D. , Newman J.A. , Niz G. , Palanque-Delabrouille N. , Rossi G. , Sanchez E. , Schlafly E.F. , Schlegel D. , Schubnell M. , Seo H. , Sprayberry D. , Tarlé G. , Weaver B.A. , Zhao C. 
Published: January 2025

Abstract
The large scale structure catalogs within DESI Data Release 1 (DR1) use nearly 6 million galaxies and quasars as tracers of the large-scale structure of the universe to measure the expansion history with baryon acoustic oscillations and the growth of structure with redshift-space distortions.
In order to take advantage of DESI's unprecedented statistical power, we must ensure that the galaxy clustering measurements are unaffected by non-cosmological density fluctuations.
One source of spurious fluctuations comes from
variation in galaxy density with spectroscopic observing conditions, lowering the redshift efficiency (and thus galaxy density) in certain areas of the sky.
We measure the uniformity of the redshift success
rate for DESI luminous red galaxies (LRG), bright galaxies (BGS) and quasars (QSO), complementing the detailed discussion of emission line galaxy (ELG) systematics in a companion paper [1].
We find small but significant fluctuations of up to 3% in redshift success rate with the effective spectroscopic signal-to-noise, and create and describe weights that remove these fluctuations.
We also describe the process to identify and remove data from certain poorly performing fibers from DESI DR1, and measure the stability of the redshift success rate with time.
Finally, we find small but significant correlations
of redshift success rate with position on the focal plane, survey speed, and number of exposures required, and show the impact of weights correcting these trends on the power spectrum multipoles and on cosmological parameters from BAO and RSD fits.
These corrections change the best-fit parameters by <15% of their statistical errors, and thus contribute negligibly to the overall DESI error budget.
Validation of the DESI 2024 Lyα forest BAO analysis using synthetic datasets
Authors: Cuceu Andrei , Herrera-Alcantar Hiram K. , Gordon Calum , Martini Paul , Guy Julien , Font-Ribera Andreu , Gonzalez-Morales Alma X. , Abdul Karim M. , Aguilar J. , Ahlen S. , Armengaud E. , Bault A. , Brooks D. , Claybaugh T. , de la Macorra A. , Doel P. , Fanning K. , Ferraro S. , Forero-Romero J.E. , Gaztañaga E. , Gontcho S.Gontcho A. , Gutierrez G. , Honscheid K. , Howlett C. , Karaçaylı N.G. , Kirkby D. , Kremin A. , Landriau M. , Le Goff J.M. , Le Guillou L. , Levi M.E. , Manera M. , Meisner A. , Miquel R. , Moustakas J. , Muñoz-Gutiérrez A. , Myers A.D. , Niz G. , Palanque-Delabrouille N. , Percival W.J. , Poppett C. , Prada F. , Pérez-Ràfols I. , Ramírez-Pérez C. , Ravoux C. , Rezaie M. , Rossi G. , Sanchez E. , Schlegel D. , Schubnell M. , Seo H. , Sprayberry D. , Tan T. , Tarlé G. , Vargas-Magaña M. , Walther M. , Weaver B.A. , Zhou R. , Zou H. 
Published: January 2025

Abstract
The first year of data from the Dark Energy Spectroscopic Instrument (DESI) contains the largest set of Lyman-α (Lyα) forest spectra ever observed. This data, collected in the DESI Data Release 1 (DR1) sample, has been used to measure the Baryon Acoustic Oscillation (BAO) feature at redshift z = 2.33. In this work, we use a set of 150 synthetic realizations of DESI DR1 to validate the DESI 2024 Lyα forest BAO measurement presented in [1]. The synthetic data sets are based on Gaussian random fields using the log-normal approximation. We produce realistic synthetic DESI spectra that include all major contaminants affecting the Lyα forest. The synthetic data sets span a redshift range 1.8 < z < 3.8, and are analysed using the same framework and pipeline used for the DESI 2024 Lyα forest BAO measurement. To measure BAO, we use both the Lyα auto-correlation and its cross-correlation with quasar positions. We use the mean of correlation functions from the set of DESI DR1 realizations to show that our model is able to recover unbiased measurements of the BAO position. We also fit each mock individually and study the population of BAO fits in order to validate BAO uncertainties and test our method for estimating the covariance matrix of the Lyα forest correlation functions. Finally, we discuss the implications of our results and identify the needs for the next generation of Lyα forest synthetic data sets, with the top priority being to simulate the effect of BAO broadening due to non-linear evolution.
Enhancing transcranial ultrasound stimulation planning with MRI-derived skull masks: a comparative analysis with CT-based processing
Authors: Zadeh Ali K , Puonti Oula , Sigurðsson Björn , Thielscher Axel , Monchi Oury , Pichardo Samuel 
Published: January 2025

Abstract

Objective. Transcranial ultrasound stimulation (TUS) presents challenges in ultrasound wave transmission through the skull, affecting study outcomes due to aberration and attenuation. While planning strategies incorporating 3D computed tomography (CT) scans help mitigate these issues, they expose participants to radiation, which can raise ethical concerns. A solution involves generating skull masks from participants’ anatomical magnetic resonance imaging (MRI). This study aims to compare ultrasound field predictions between CT-derived and MRI-derived skull masks in TUS planning. Approach. Five participants with a range of skull density ratios (SDRs: 0.31, 0.42, 0.55, 0.67, and 0.79) were selected, each having both CT and T1/T2-weighted MRI scans. Ultrasound simulations were performed using BabelBrain software with a single-element transducer (diameter = 50 mm, F# = 1) at 250, 500, and 750 kHz frequencies. CT scans were used to generate maps of the skull’s acoustic properties. The MRI scans were processed using the Charm segmentation tool from the SimNIBS tool suite using default and custom settings adapted for better skull segmentation. Ultrasound was adjusted to target 30 mm below the skull’s surface at 54 electroencephalogram (EEG) locations. Main Results. The custom setting in Charm significantly improved the Dice coefficient between MRI- and CT-derived masks when compared to the default setting (p < 0.001). The maximum pressure error significantly decreased in the custom setting compared to the default setting (p < 0.001). Additionally, the focus location error median across different SDRs averaged 2.32, 1.45, and 1.57 mm in default and 2.08, 1.38, and 1.44 mm in custom conditions for 250 kHz, 500 kHz, and 750 kHz respectively. Significance. MRI-derived skull masks offer satisfactory accuracy at many EEG sites, and using custom settings can further enhance this accuracy. However, significant errors at specific locations highlight the importance of carefully considering stimulation location when choosing between CT- and MRI-derived skull modeling.
Diffusion transformer-augmented fMRI functional connectivity for enhanced autism spectrum disorder diagnosis
Authors: Zhao Haokai , Lou Haowei , Yao Lina , Zhang Yu 
Published: January 2025

Abstract

Objective. Functional magnetic resonance imaging (fMRI) is often modeled as networks of Regions of Interest and their functional connectivity to study brain functions and mental disorders. Limited fMRI data due to high acquisition costs hampers recognition model performance. We aim to address this issue using generative diffusion models for data augmentation. Approach. We propose Brain-Net-Diffusion, a transformer-based latent diffusion model to generate realistic functional connectivity for augmenting fMRI datasets and evaluate its impact on classification tasks. Main results. The Brain-Net-Diffusion effectively generates connectivity patterns resembling real data and significantly enhances classification performance. Augmentation using Brain-Net-Diffusion increased downstream autism spectrum disorder classification accuracy by 4.3% compared to no augmentation. It also outperformed other augmentation methods, with accuracy improvements ranging from 1.3% to 2.2%. Significance. Our approach demonstrates the effectiveness of diffusion models for fMRI data augmentation, providing a robust solution for overcoming data scarcity in functional connectivity analysis. To facilitate further research, we have made our code publicly available at https://github.com/JoeZhao527/brain-net-diffusion.
Efficient calculation of self magnetic field, self-force, and self-inductance for electromagnetic coils with rectangular cross-section
Authors: Landreman Matt , Hurwitz Siena , Antonsen Thomas M. 
Published: January 2025

Abstract
For designing high-field electromagnets, the Lorentz force on coils needs to be computed in order to design suitable support structures, and the inductance should be computed to evaluate the stored energy and dynamics. Also, the magnetic field and its variation inside the conductor is of interest for computing stress and strain, and due to superconducting quench limits. For these force, inductance, energy, and internal field calculations, the coils cannot be naively approximated as infinitesimally thin filaments due to divergences when the source and evaluation points coincide, so more computationally demanding calculations are usually required, resolving the finite cross-section of the conductors. Here, we present a new alternative method that enables the internal magnetic field vector, self-force, and self-inductance to be computed rapidly and accurately within a 1D filament model. The method is applicable to coils for which the curve center-line can have general noncircular shape, as long as the conductor width is small compared to the radius of curvature. This paper extends a previous calculation for circular-cross-section conductors (Hurwitz et al 2024 IEEE Trans. Magn.) to consider the case of rectangular cross-section. The reduced model is derived by rigorous analysis of the singularity, regularizing the filament integrals such that they match the true high-dimensional integrals at high coil aspect ratio. The new filament model exactly recovers analytic results for a circular coil, and is shown to accurately reproduce full finite-cross-section calculations for a non-planar coil of a stellarator magnetic fusion device. Due to the efficiency of the model here, it is well suited for use inside design optimization.
Cleopatra: a 12-channel recycling integrator ASIC for the
readout of hydrogenated amorphous silicon detectors in radiotherapy dosimetry
Authors: Mazza G. , Wheadon R. , Lenta F. , Buti C. , Fabi M. , Grimani C. , Pallotta S. , Sabbatini F. , Talamonti C. , Villani M. , Aziz S. , Calcagnile L. , Caricato A.P. , Martino M. , Maruccio G. , Monteduro A.G. , Quarta G. , Rizzato S. , Catalano R. , Cirrone G.A.P. , Cuttone G. , Guarrera M.C. , Petringa G. , Frontini L. , Liberali V. , Stabile A. , Vasquez M. , Croci T. , Ionica M. , Kanxheri K. , Menichelli M. , Morozzi A. , Moscatelli F. , Passeri D. , Pedio M. , Peverini F. , Placidi P. , Servoli L. , Tosti L. , Zema N. , Caputo D. , De Cesare G. , Lovecchio N. , Nascetti A. , Calvo D. , Cirio R. , De Remigis P. , Dunand S. , Thomet J.E. , Large M. , Petasecca M. , Bashiri A. , Piccolo L. , Wyrsch N. ,   the HASPIDE collaboration
Published: January 2025

Abstract
The Cleopatra ASIC is a 12-channel prototype ASIC for the readout of hydrogenated
amorphous silicon sensors used for real-time dosimetry in radiation diagnostic and radiation
therapy. The architecture is based on a current to frequency conversion based on the recycling
integrator principle in order to cover a dynamic range of four orders of magnitude with high
linearity. Three different input amplifier configurations have been implemented in order to check
the trade-off between detector capacitance and maximum output frequency. Cleopatra has been
designed in CMOS 28 nm technology and succesfully tested in laboratory.
Development of a transportable neutron imager for localization of radioactive sources
Authors: Altıngün A.M. , El Bitar Z. , Gendre Q. , Buridon V. , Schoepff V. , Carrel F. , Amoyal G. , Kanj A. , Pellicioli M. , Schuler J. 
Published: January 2025

Abstract
Locating radioactive hot spots presents a significant challenge for the nuclear industry and security applications, such as waste management, decommissioning, radiation protection, and the management of nuclear accidents. The detection of fast-neutron emissions offers an alternative technique to gamma imaging for verifying the location of radioactive materials, particularly in cases where gamma imagers face challenges in detection. In this study, we present the performance of a prototype gamma-neutron imaging system based on a custom-fabricated plastic scintillator, designed to effectively discriminate between signals from gamma radiation, fast neutrons, and thermal neutrons.

We conducted Geant4 simulations to investigate neutron interactions within the plastic scintillator and compared the simulation results with experimental data. Additionally, we performed experiments on the prototype using a proton beam at the CYRCé facility at IPHC, utilizing a CMOS Monolithic Active Pixel Sensor (MAPS) called MIMOSIS to analyze the beam profile. Through these efforts, we examined neutron interactions with our scintillator, validated the prototype's imaging capabilities under proton beam exposure, and conducted a calibration study of its energy response.
A high accuracy CMOS peak detection and holder ASIC for neutron detectors
Authors: Ren Jiayi , Liu Hongbin , Yin Weigang , Li Qicai , Lai Yanling , Yu Li , Zeng Lixin , Luo Hong , Chen Shaojia , Shen Peixun , Jiang Xingfen , Zhou Jianrong , Zhuang Jian , Zhao Yubin , Sun Zhijia 
Published: January 2025

Abstract
With the completion and operation of a series of high-performance neutron sources, such as the China Spallation Neutron Source (CSNS), various neutron scattering spectrometers have continuously increased their performance requirements. One important aspect is to reduce collisions between scattered neutrons and air molecules during neutron scattering experiments, thereby reducing background noise and obtaining highly accurate experimental measurement results. This paper presents an application-specific integrated circuit (ASIC) dedicated to position-sensitive Helium-3 tubes neutron detector, which introduces peak detection and holder (PDH) circuits on the basis of traditional front-end electronics. Through a specific design, the switches and holding capacitor of the PDH module are isolated, ensuring that the holding voltage is not affected by switch noise, and maximizing the measurement accuracy of the PDH module. The 8 channel ASIC, realized in 0.18 μm CMOS technology, has a 10 fC to 1 pC input signal range with a linearity error within 0.22% to 1%. The PDH module is supplied with a single voltage of 1.8 V with a total power consumption of 350 μW with a layout area of 361 μm × 68 μm. The ASIC further enhances system integration, allowing the analog-to-digital conversion module to employ low-speed ADCs, thereby reducing the overall power consumption of the readout system. This enables the entire detector to operate in a vacuum environment, providing a new electronic readout solution for future neutron scattering and imaging experiments.
PMEDM process parameter optimization for machining superalloy MONEL 400
Authors: Kumar Abhishek , Nikam Manoj , Jagadeesha T , Rehman Ateekh Ur , Bhongade Ajay S , Shivagond Teli 
Published: January 2025

Abstract
MONEL 400, widely used in industries such as high-temperature applications, chemical processing, automotive, and marine sectors, presents significant machining challenges due to its high strength and tendency for work-hardening. This research explores powder-mixed electrical discharge machining (PMEDM), a modern technique incorporating conductive metal powders, specifically graphite and silicon, combined with dielectric fluid to improve machining performance. The study investigates into how to machine MONEL 400 with copper as the cathode, focusing on important process parameters such as powder concentration, peak-current, and pulse on duration. This study also compared impact of PMEDM to conventional EDM, and results demonstrated improvements in material removal rate, tool wear rate, and surface roughness. Graphite powder significantly reduced tool wear, while silicon powder significantly enhanced surface finish. Using Buckingham’s theorem and regression analysis, this study presented semi-empirical models for the rate of material removal and looks at how the powder additives’ dielectric properties have changed to improve performance. The research aims to improve sustainable machining practices while providing environmental benefits.
Comparing three generations of D-Wave quantum annealers for minor embedded combinatorial optimization problems
Authors: Pelofske Elijah 
Published: January 2025

Abstract
Quantum annealing (QA) is a novel type of analog computation that aims to use quantum mechanical fluctuations to search for optimal solutions of Ising problems. QA in the transverse Ising model, implemented on D-Wave quantum processing units, are available as cloud computing resources. In this study we report concise benchmarks across three generations of D-Wave quantum annealers, consisting of four different devices, for the NP-hard discrete combinatorial optimization problems unweighted maximum clique and unweighted maximum cut on random graphs. The Ising, or equivalently quadratic unconstrained binary optimization, formulation of these problems do not require auxiliary variables for order reduction, and their overall structure and weights are not highly variable, which makes these problems simple test cases to understand the sampling capability of current D-Wave quantum annealers. All-to-all minor embeddings of size 52, with relatively uniform chain lengths, are used for a direct comparison across the Chimera, Pegasus, and Zephyr device topologies. A grid-search over annealing times and the minor embedding chain strengths is performed in order to determine the level of reasonable performance for each device and problem type. Experiment metrics that are reported are approximation ratios for non-broken chain samples, chain break proportions, and time-to-solution for the maximum clique problem instances. How fairly the quantum annealers sample optimal maximum cliques, for instances which contain multiple maximum cliques, is quantified using entropy of the measured ground state distributions. The newest generation of quantum annealing hardware, which has a Zephyr hardware connectivity, performed the best overall with respect to approximation ratios and chain break frequencies.