The Astrophysical Journal Supplement Series最新文献_第8页

Advancing Solar Energetic Particle Event Prediction through Survival Analysis and Cloud Computing. I. Kaplan–Meier Estimation and Cox Proportional Hazards Modeling 通过生存分析和云计算推进太阳高能粒子事件预测。I. Kaplan-Meier 估计和 Cox 比例危害模型

The Astrophysical Journal Supplement Series Pub Date : 2024-06-01 DOI: 10.3847/1538-4365/ad3fba

India Jackson, Petrus Martens

{"title":"Advancing Solar Energetic Particle Event Prediction through Survival Analysis and Cloud Computing. I. Kaplan–Meier Estimation and Cox Proportional Hazards Modeling","authors":"India Jackson, Petrus Martens","doi":"10.3847/1538-4365/ad3fba","DOIUrl":"https://doi.org/10.3847/1538-4365/ad3fba","url":null,"abstract":"Solar energetic particles (SEPs) pose significant challenges to technology, astronaut health, and space missions. This initial paper in our two-part series undertakes a comprehensive analysis of the time to detection for SEPs, applying advanced statistical techniques and cloud-computing resources to deepen our understanding of SEP event probabilities over time. We employ a range of models encompassing nonparametric, semiparametric, and parametric approaches, such as the Kaplan–Meier estimator and Cox Proportional Hazards models. These are complemented by various distribution models—including exponential, Weibull, lognormal, and log-logistic distributions—to effectively tackle the challenges associated with “censored data,” a common issue in survival analysis. Employing Amazon Web Services and Python’s “lifelines” and “scikit-survival” libraries, we efficiently preprocess and analyze large data sets. This methodical approach not only enhances our current analysis, but also sets a robust statistical foundation for the development of predictive models, which will be the focus of the subsequent paper. In identifying the key determinants that affect the timing of SEP detection, we establish the vital features that will inform the machine-learning (ML) techniques explored in the second paper. There, we will utilize advanced ML models—such as survival trees and random survival forests—to evolve SEP event prediction capabilities. This research is committed to advancing space weather, strengthening the safety of space-borne technology, and safeguarding astronaut health.","PeriodicalId":22368,"journal":{"name":"The Astrophysical Journal Supplement Series","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141410498","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Erratum: “Photometric Selection of Unobscured QSOs at the Ecliptic Poles: KMTNet in the South Field and Pan-STARRS in the North Field” (2023, ApJS, 268, 57) 勘误："黄道两极无遮挡 QSO 的光度选择：南磁场的 KMTNet 和北磁场的 Pan-STARRS"（2023 年，ApJS, 268, 57）：南场的KMTNet和北场的Pan-STARRS"（2023年，ApJS，268，57）

The Astrophysical Journal Supplement Series Pub Date : 2024-06-01 DOI: 10.3847/1538-4365/ad487c

Woowon Byun, Minjin Kim, Y. Sheen, Dongseob Lee, L. C. Ho, Jongwan Ko, K. Seon, H. Shim, Dohyeong Kim, Yongjung Kim, J. Lee, Hyunjin Jeong, Jong-Hak Woo, Woong-Seob Jeong, Byeong-Gon Park, Sang Chul Kim, Yongseok Lee, S. Cha, Hyunmi Song, D. Son, Yujin Yang

引用次数: 0

A Sample of Am and Ap Candidates from LAMOST DR10 (v1.0) Based on the Ensemble Regression Model 基于集合回归模型的 LAMOST DR10（v1.0）Am 和 Ap 候选样本

The Astrophysical Journal Supplement Series Pub Date : 2024-06-01 DOI: 10.3847/1538-4365/ad4107

Hai-Feng 海峰 Yang 杨, Rui 瑞 Wang 王, Jiang-Hui 江辉 Cai 蔡, A-Li 阿理 Luo 罗, Bing 冰 Du 杜, Yan-Ting 艳婷 He 贺, Mei-Hong 美红 Su 苏, Chen-Hui 晨辉 Shi 史, Xu-Jun 旭俊 Zhao 赵, Ya-Ling 亚玲 Xun 荀, Yi-Nan 艺楠 Yuan 员

{"title":"A Sample of Am and Ap Candidates from LAMOST DR10 (v1.0) Based on the Ensemble Regression Model","authors":"Hai-Feng 海峰 Yang 杨, Rui 瑞 Wang 王, Jiang-Hui 江辉 Cai 蔡, A-Li 阿理 Luo 罗, Bing 冰 Du 杜, Yan-Ting 艳婷 He 贺, Mei-Hong 美红 Su 苏, Chen-Hui 晨辉 Shi 史, Xu-Jun 旭俊 Zhao 赵, Ya-Ling 亚玲 Xun 荀, Yi-Nan 艺楠 Yuan 员","doi":"10.3847/1538-4365/ad4107","DOIUrl":"https://doi.org/10.3847/1538-4365/ad4107","url":null,"abstract":"Large samples of Am and Ap stars are helpful in studying the interplay between phenomena like atomic diffusion, magnetic fields, and stellar rotation in stellar astrophysics. Existing samples of Am and Ap stars, mostly obtained from spectral data with a signal-to-noise ratio in the g band (S/Ng) greater than 50, can benefit from expansion by exploring spectra with lower S/Ng. Therefore, this paper proposes an ensemble regression model applicable to spectra with a minimum S/Ng of 30. Using the model, we identify 21,361 Am candidates, of which 11,614 are new, and 6182 Ap candidates, of which 4978 are new, from LAMOST DR10. The Am sample size has increased by 60% and the Ap sample size has increased by 180% compared to the previous sample. In terms of effective temperature (T eff), the Am candidates range mainly from 6000 to 8500 K, while the Ap candidates range from 6000 to 11,700 K. The surface gravity ( logg ) distributions for Am and Ap candidates differ in the range of 3.25–4.75 dex. The number of Am candidates increases stepwise, in contrast to the relatively uniform distribution of Ap candidates across the entire surface gravity range. Regarding metallicity ([Fe/H]), Am candidates typically range from −0.75 to 0.38 dex, peaking near 0 dex, while Ap candidates are distributed from −1.38 to 0.38 dex, with a peak near −0.5 dex.","PeriodicalId":22368,"journal":{"name":"The Astrophysical Journal Supplement Series","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141396125","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Theoretical Study of Electron Capture, Excitation, and Ionization Processes in H+−H(2l) Collisions H+-H(2l) 碰撞中电子俘获、激发和电离过程的理论研究

The Astrophysical Journal Supplement Series Pub Date : 2024-06-01 DOI: 10.3847/1538-4365/ad3633

Y. Wang, K. Wang, L. Liu, Y. Wu, F. Wang, J. G. Wang

{"title":"Theoretical Study of Electron Capture, Excitation, and Ionization Processes in H+−H(2l) Collisions","authors":"Y. Wang, K. Wang, L. Liu, Y. Wu, F. Wang, J. G. Wang","doi":"10.3847/1538-4365/ad3633","DOIUrl":"https://doi.org/10.3847/1538-4365/ad3633","url":null,"abstract":"The processes of single-electron charge exchange, excitation, and ionization during proton impact on H(2l) are investigated. We employ two different theoretical methods that are suitable for different collision energy regions: the full quantum-mechanical molecular orbital close-coupling method for energies from 0.001 to 1 keV u−1 and the two-center atomic orbital close-coupling (TC-AOCC) method for energies between 0.3 and 100 keV u−1. For charge exchange and excitation processes, the total and nl-resolved cross sections to the final reaction channels of H (nl, n = 1–4) have been obtained over a broad energy region. Moreover, the ionization cross sections in the TC-AOCC calculation are also reported for both H(2s) and H(2p) initial target states. The present results are all compared with those from other sources when available. It is found that the magnitude and energy behavior of nl-resolved excitation cross sections for H+–H(2p) collisions are significantly distinct from those of the H(2s) initial state in the entire energy range considered, particularly in the low-energy region. The energy behaviors of the nl-resolved charge exchange cross sections from the H(2p) initial state are similar to those from the H(2s) initial state, but their magnitudes are larger. The present accurate cross-section data are anticipated to provide insight into the research of astrophysics and controlled fusion plasmas.","PeriodicalId":22368,"journal":{"name":"The Astrophysical Journal Supplement Series","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141403554","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Multiobject Spectroscopy of Galaxy Clusters at z ∼ 0.95 in the Ultra Deep Survey Field with Different Star Formation Properties and Large-scale Environments 对超深巡天观测场中 z ∼ 0.95 星级、具有不同恒星形成特性和大尺度环境的星系团进行多目标光谱分析

The Astrophysical Journal Supplement Series Pub Date : 2024-06-01 DOI: 10.3847/1538-4365/ad45f8

Seong-Kook Lee, Myungshin Im, Bomi Park, M. Hyun, I. Paek, Dohyeong Kim

{"title":"Multiobject Spectroscopy of Galaxy Clusters at z ∼ 0.95 in the Ultra Deep Survey Field with Different Star Formation Properties and Large-scale Environments","authors":"Seong-Kook Lee, Myungshin Im, Bomi Park, M. Hyun, I. Paek, Dohyeong Kim","doi":"10.3847/1538-4365/ad45f8","DOIUrl":"https://doi.org/10.3847/1538-4365/ad45f8","url":null,"abstract":"While galaxy clusters are dominated by quiescent galaxies in the local Universe, they show a wide range in quiescent galaxy fraction (QF) at higher redshifts. Here we present the discovery of two galaxy clusters at z ∼ 0.95 with contrasting QFs despite having similar masses (log (M 200/M ⊙) ∼ 14) and spectra and redshifts of 29 galaxies in these clusters and 76 galaxies in the surrounding area. The clusters are found in the Ultra Deep Survey field and confirmed through multiobject spectroscopic observation using the Inamori Magellan Areal Camera and Spectrograph on the Magellan telescope. The two clusters exhibit QFs of 0.094−0.032+0.11 and 0.38−0.11+0.14 , respectively. Analysis of large-scale structures (LSSs) surrounding these clusters finds that properties of these clusters are consistent with the anticorrelation trend between the QF and the extent of surrounding LSS, found in Lee et al., which can be interpreted as a result of the replenishment of young, star-forming galaxies keeping the QF low when galaxy clusters are accompanied by rich surrounding environments.","PeriodicalId":22368,"journal":{"name":"The Astrophysical Journal Supplement Series","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141414564","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Numerical Modeling of Energetic Charged-particle Transport with SPECTRUM Software: General Approach and Artificial Effects due to Field Discretization 用 SPECTRUM 软件建立高能带电粒子输运的数值模型：一般方法和场离散化引起的人为效应

The Astrophysical Journal Supplement Series Pub Date : 2024-06-01 DOI: 10.3847/1538-4365/ad4637

J. A. Guzman, V. Florinski, G. Tóth, S. Sharma, B. van der Holst, M. Opher

引用次数: 0

Erratum: “Zero and Extremely Low-metallicity Rotating Massive Stars: Evolution, Explosion, and Nucleosynthesis Up to the Heaviest Nuclei” (2024, ApJS, 270, 28) 勘误："零金属性和极低金属性旋转大质量恒星：进化、爆炸和核合成，直至最重的核" (2024, ApJS, 270, 28)

The Astrophysical Journal Supplement Series Pub Date : 2024-06-01 DOI: 10.3847/1538-4365/ad4f7d

L. Roberti, M. Limongi, A. Chieffi

引用次数: 0

A Catalog of Early-type Runaway Stars from LAMOST DR8 来自 LAMOST DR8 的早期型失控恒星表

The Astrophysical Journal Supplement Series Pub Date : 2024-06-01 DOI: 10.3847/1538-4365/ad46f8

Yanjun Guo, Luqian 璐茜 Wang 王, C. Liu 刘, Y. Wu 吴, Z. Han 韩, X. Chen 陈

{"title":"A Catalog of Early-type Runaway Stars from LAMOST DR8","authors":"Yanjun Guo, Luqian 璐茜 Wang 王, C. Liu 刘, Y. Wu 吴, Z. Han 韩, X. Chen 陈","doi":"10.3847/1538-4365/ad46f8","DOIUrl":"https://doi.org/10.3847/1538-4365/ad46f8","url":null,"abstract":"Runaway stars are OB-type stars ejected from their birthplace with large peculiar velocities. The leading hypothesis addressed in their formation includes the supernova ejection mechanism and the dynamic ejection scenario. Identification of runaway populations is the first step to investigating their formation and evolution. Here we present our work of searching for Galactic runaway candidate stars from the Large sky Area Multi-Object fiber Spectroscopic Telescope (LAMOST) Medium Resolution Survey Data Release 8 (DR8) database. After studying the kinematic properties for a collection of 4432 early-type stars, predominantly B-type stars, using radial velocity measurements from LAMOST DR8 and astrometric solutions made by Gaia Data Release 3, we identified 229 runaway candidate stars. They span a wide distribution in projected rotational velocities. We investigated the Galactic spatial distribution of the runaway population and noticed that most of them likely reside within the Galactic thin disk. Based upon analyzing the Doppler shifts of the candidate stars, we found two binary runaway candidates displaying velocity variations with estimated orbital periods of 40 and 61 days.","PeriodicalId":22368,"journal":{"name":"The Astrophysical Journal Supplement Series","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141407797","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Sample and Statistical Analysis on NEOWISE Variability of ATLASGAL Sources 关于ATLASGAL源的NEOWISE变异性的样本和统计分析

The Astrophysical Journal Supplement Series Pub Date : 2024-06-01 DOI: 10.3847/1538-4365/ad41e2

Ying Lu, Xi Chen, Shijie Song, Jun-Ting Liu, Tian Yang, You-Xin Wang, Yan-Kun Zhang, Shi-Jie Zhang

{"title":"Sample and Statistical Analysis on NEOWISE Variability of ATLASGAL Sources","authors":"Ying Lu, Xi Chen, Shijie Song, Jun-Ting Liu, Tian Yang, You-Xin Wang, Yan-Kun Zhang, Shi-Jie Zhang","doi":"10.3847/1538-4365/ad41e2","DOIUrl":"https://doi.org/10.3847/1538-4365/ad41e2","url":null,"abstract":"This study focuses on the analysis of mid-infrared variability in a sample of high-mass young stellar objects (YSOs) associated with the cataloged sources from the APEX Telescope Large Area Survey of the Galaxy (ATLASGAL). The Near-Earth Object Wide-field Infrared Survey Explorer Reactivation Mission (NEOWISE) database was used to explore the long-term mid-infrared variability of these high-mass YSOs at a half-year scale. After matching with NEOWISE photometric measurements, a total of 2230 ATLASGAL sources were selected for the variability analysis, out of which 717 were identified as variables. The derived proportions of variables at different evolutionary stages show that the variability rate of high-mass YSOs is highest during the YSO stage and decreases with evolution toward the H ii region stage, resembling the behavior of low-mass YSOs. The variables can be classified into six types based on their light curves, divided into two categories: secular (linear, sin, sin+linear) and stochastic variables (burst, drop, and irregular). The magnitude–color variations observed in ∼160 secular variables can be mainly divided into “bluer when brighter/redder when dimming” and “redder when brighter/bluer when dimming,” likely originating from changes in accretion rate or the effect of extinction due to obscuration. Moreover, several episodic accretion candidates were selected for further observational studies.","PeriodicalId":22368,"journal":{"name":"The Astrophysical Journal Supplement Series","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141411714","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Erratum: “Stellar Loci. VII. Photometric Metallicities of 5 Million FGK Stars Based on GALEX GR6+7 AIS and Gaia EDR3” (2024, ApJS, 271, 26) 勘误："Stellar Loci.VII.基于 GALEX GR6+7 AIS 和 Gaia EDR3 的 500 万 FGK 恒星的光度金属性"（2024 年，ApJS，271，26）

The Astrophysical Journal Supplement Series Pub Date : 2024-06-01 DOI: 10.3847/1538-4365/ad488b

Xue Lu, Haibo Yuan, Shuai Xu, Ruoyi Zhang, K. Xiao, Yang Huang, T. Beers, Jihye Hong

引用次数: 0