We present new high resolution (R>50,000) absorption measurements of the NaI doublet (5889 - 5895A) along 482 nearby sight-lines, in addition to 807 new measurements of the CaII K (3933A) absorption line. We have combined these new data with previously reported measurements to produce a catalog of absorptions towards a total of 1857 early-type stars located within 800pc of the Sun. Using these data we have determined the approximate 3-dimensional spatial distribution of neutral and partly ionized interstellar gasdensity within a distance-cube of 300pc from the Sun. All newly recorded spectra were analyzed by means of a multi-component line profile-fitting program, in most cases using simultaneous fits to the line doublets. Normalized absorption profiles were fitted by varying the velocity, doppler width and column density for all intervening interstellar clouds. The resulting total column densities were then used in conjunction with the Hipparcos distances of the target stars to construct inversion maps of the 3-D spatial density distribution of the NaI and CaII bearing gas. A plot of the equivalent width of NaI versus distance reveals a wall of neutral gas at ~80pc that can be associated with the boundary wall to the central rarefied Local Cavity region. In contrast, a similar plot for the equivalent width of CaII shows no sharply increasing absorption at 80pc, but instead we observe a slowly increasing value of CaII equivalent width with increasing sight-line distance sampled.
Comparing absorption from classic tracers of the diffuse interstellar medium at optical and radio wavelengths along the same sightlines
目的比较从漫射星际介质沿同一视线的射电和光学吸收线剖面获得的信息。方法我们比较了新的和现有的21 cm HI和3.4 mm HCO+剖面与光学示踪剂Ca II，NaI，和KI来自Tappe（2004）未发表的论文。结果与太阳丰度相比，光学追踪的原子都是严重亏损的，只有HI和HCO+的积分光学深度与E（B-V）有很好的相关性。HCO+是迄今为止运动学分布最有限的物种，其最西的线依次为KI、HI、NaI和CaII。CaII在柱密度和运动学上都有单独的行为，因为它对更宽范围的温暖气体进行采样。冷中性介质NaI，KI，HI和HCO+的示踪剂在统计上共享相同的运动学空间，而在丰度上几乎没有相同程度的相关性。N（NaI）和N（KI）是相关的，是HI和HCO+的综合光学深度，但光学和无线电示踪剂之间的丰度相关性没有看到。在唯一的方向与测量的CH+的配置文件，2公里/秒的速度之间的CH+和CH，通常被解释为冲击气体的迹象，模仿HI相对于HCO+的移位。CH和HCO+出现在两条视线上的比例N（CH）/N（HCO+）=14.6和21.1，光学测量的N（CH），与之前在无线电和亚毫米波长确定的平均值12相比。
The Gaia-ESO Survey: Extracting diffuse interstellar bands from cool star spectra, DIB-based interstellar medium line-of-sight structures at the kpc scale
No Evidence for Nearby Circumstellar Material in the Type Ia Supernova 2025rbs
University of California, Davis（加州大学戴维斯分校）；University of California, San Diego（加州大学圣地亚哥分校）；Rutgers, The State University of New Jersey（新泽西州立罗格斯大学）；Gemini Observatory/NSF’s NOIRLab（双子座天文台/美国国家光学红外天文实验室）；Steward Observatory, University of Arizona（亚利桑那大学斯图尔德天文台）；NASA Exoplanet Science Institute / Caltech-IPAC（NASA系外行星科学研究所/加州理工学院IPAC）；NSF’s NOIRLab（美国国家光学红外天文实验室）
The Synthetic Absorption Line Spectral Almanac (SALSA)
Universität Heidelberg（海德堡大学）；European Southern Observatory（欧洲南方天文台）；Aix Marseille Univ, CNRS, CNES, LAM（艾克斯-马赛大学）；Institut für Physik und Astronomie, Universität Potsdam（波茨坦大学物理与天文学研究所）；Universidad de Chile（智利大学）；North Carolina State University（北卡罗来纳州立大学）；Chinese Academy of Sciences South America Center for Astronomy, National Astronomical Observatories（中国科学院南美天文中心，国家天文台）；New Mexico State University（新墨西哥州立大学）；Swinburne University of Technology（斯威本科技大学）；Kavli IPMU (WPI), UTIAS, The University of Tokyo（东京大学）
本文介绍了首个大规模的模拟光谱学调查，通过宇宙流体动力学模拟生成气体吸收视线的光谱，旨在研究银河系周围星际介质、 circumgalactic medium 和 intergalactic medium 的特性，提供了广泛的应用场景和科学目标。
Peering down the barrel with DESI DR2: 10 000+ inflows at $z$ < 0.6 reveal how galaxies accrete cold gas
Aix Marseille Univ, CNRS, CNES, LAM（艾克斯马赛大学）；Department of Physics & Astronomy, University College London（伦敦大学学院物理与天文系）；Max-Planck-Institut für Radioastronomie（马克斯·普朗克射电天文研究所）；Department of Physics and Astronomy, Siena University（锡耶纳大学物理与天文系）；National Astronomical Observatories, Chinese Academy of Sciences（中国科学院国家天文台）；Kavli Institute for the Physics and Mathematics of the Universe (WPI), The University of Tokyo Institutes for Advanced Study (UTIAS), The University of Tokyo（东京大学宇宙物质研究前沿中心）；Lawrence Berkeley National Laboratory（劳伦斯伯克利国家实验室）；Department of Physics, Boston University（波士顿大学物理系）；Dipartimento di Fisica “Aldo Pontremoli”, Università degli Studi di Milano（米兰大学阿尔多·蓬特罗莫利物理系）；INAF-Osservatorio Astronomico di Brera（意大利国家天体物理研究所布雷拉天文台）
