The Apache Point Observatory Galactic Evolution Experiment: First Detection of High Velocity Milky Way Bar Stars
David L. Nidever, Gail Zasowski, Steven R. Majewski, Jonathan Bird, Annie C. Robin, Inma Martinez-Valpuesta, Rachael L. Beaton, Ralph Schoenrich, Mathias Schult… 展开作者
David L. Nidever, Gail Zasowski, Steven R. Majewski, Jonathan Bird, Annie C. Robin, Inma Martinez-Valpuesta, Rachael L. Beaton, Ralph Schoenrich, Mathias Schultheis, John C. Wilson, Michael F. Skrutskie, Robert W. O'Connell, Matthew Shetrone, Ricardo P. Schiavon, Jennifer A. Johnson, Benjamin Weiner, Ortwin Gerhard, Donald P. Schneider, Carlos Allende Prieto, Kris Sellgren, Dmitry Bizyaev, Howard Brewington, Jon Brinkmann, Daniel J. Eisenstein, Peter M. Frinchaboy, Ana Elia Garcia Perez, Jon Holtzman, Fred R. Hearty, Elena Malanushenko, Viktor Malanushenko, Demitri Muna, Daniel Oravetz, Kaike Pan, Audrey Simmons, Stephanie Snedden, Benjamin A. Weaver
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7 pages, 4 figures, accepted for publication in ApJ Letters
Commissioning observations with the Apache Point Observatory Galactic Evolution Experiment (APOGEE), part of the Sloan Digital Sky Survey III, have produced radial velocities (RVs) for ~4700 K/M-giant stars in the Milky Way bulge. These high-resolution (R \sim 22,500), high-S/N (>100 per resolution element), near-infrared (1.51-1.70 um; NIR) spectra provide accurate RVs (epsilon_v~0.2 km/s) for the sample of stars in 18 Galactic bulge fields spanning -1<l<20 deg, |b|<20 deg, and dec>-32 deg. This represents the largest NIR high-resolution spectroscopic sample of giant stars ever assembled in this region of the Galaxy. A cold (sigma_v~30 km/s), high-velocity peak (V_GSR \sim +200 km/s) is found to comprise a significant fraction (~10%) of stars in many of these fields. These high RVs have not been detected in previous MW surveys and are not expected for a simple, circularly rotating disk. Preliminary distance estimates rule out an origin from the background Sagittarius tidal stream or a new stream in the MW disk. Comparison to various Galactic models suggests that these high RVs are best explained by stars in orbits of the Galactic bar potential, although some observational features remain unexplained.
MaNGA: Mapping Nearby Galaxies at Apache Point Observatory
MANGA(Mapping Nearby Galerkin at APO)是第四代斯隆数字巡天(SDSS-IV)中的星系积分场光谱巡天。它将使用17个不同大小的纤维束,绘制10,000个附近星系中气体和恒星的成分和运动学。MaNGA的目标是为星系形成和演化提供新的见解,并为当前和未来的高红移研究提供本地基准。
Target Selection for the Apache Point Observatory Galactic Evolution Experiment (APOGEE)
Apache Point Observatory星系演化实验(APOGEE)是一项高分辨率的红外光谱调查,覆盖所有银河系环境(即,膨胀,磁盘和晕),与约束银河系的动力学和化学演化模型的主要目标。APOGEE利用红外波长消光效应的减少,以前所未有的细节水平观察银河系内部和凸起。巡天的广泛空间和波长覆盖范围使APOGEE数据的用户能够解决许多银河系结构和恒星星族问题。在本文中,我们描述了APOGEE的目标计划,并记录其各种目标类,提供必要的背景和参考信息,分析样品的APOGEE数据与意识强加的选择标准和产生的样本属性。APOGEE的主要样本由约100,000颗红巨星组成,选择这些样本是为了最大限度地减少年龄和金属丰度方面的观测偏差。我们提出的方法和考虑因素,推动选择这个样本,并评估的准确性,效率和选择和采样算法的注意事项。我们还描述了有助于APOGEE样本的其他目标类别,包括许多辅助科学计划,我们概述了将包含在公共数据发布中的目标数据。
The Apache Point Observatory Catalog of Optical Diffuse Interstellar Bands
为了在4,000到9,000光年之间建立一个新的、更全面的DIB星表,我们基于HD 183143和HD 204827的观测重新审视了Atlas星表(Hobbs et al. 2008 and 2009)。选择了25条中度到高度红化的视线,对背景恒星和星际环境的各种光谱类型进行采样。这些光谱的中值SNR在6,400 nm附近为~ 1,300。与阿特拉斯星表相比,发现了22个新的DIB,并调整了27组DIB的边界,从而更新了包含559个DIB的星表,我们称之为Apache Point Observatory Catalog of Optical Diffuse Interstellar Bands。然后根据该目录进行测量。我们发现我们的调查在5,500到7,000光年之间最敏感,这主要是由于光谱的局部信噪比,相对缺乏干扰恒星线,以及大地残差的弱点。对于我们的数据样本,在给定的视线中检测到的DIB的数量主要取决于EB-V,而不是背景恒星的光谱类型。观察到对fH 2的一些依赖性,但由于数据样本的大小有限,因此不太确定。每个DIB在不同视线上的波长变化一般大于已知星际线CH+、CH和KI的波长变化。这些变化可能是由于测量中的固有误差,或视线之间的速度分量的差异。
The Apache Point Observatory extra-Galactic Evolution Experiment (APOeGEE): Chemical Abundance Trends for Seven Dwarf Spheroidal Galaxies in the APOGEE Survey
University of California Observatories, University of California Santa Cruz(加州大学天文台,加州大学圣克鲁兹分校);Space Telescope Science Institute(太空望远镜科学研究所);New Mexico State University(新墨西哥州立大学);Steward Observatory, University of Arizona(斯图尔德天文台,亚利桑那大学);University of Virginia(弗吉尼亚大学);University of Washington(华盛顿大学);Liverpool John Moores University(利物浦约翰摩尔斯大学);NOIRLab(NOIR天文实验室)
Apache Point Observatory follow-up of ACcelerating Candidate ExopLanet host Stars (APO ACCELS): Ages for 166 Accelerating Stars in the Northern Hemisphere
Predicted Stellar Kinematics of a Kiloparsec-Scale Nuclear Disc (or Ring) in the Milky Way
在Debattista et al.(2015)中,我们提出一个千秒差距尺度的核盘是Apache Point Observatory星系演化实验(APOGEE)在凸起的正向角上观察到的恒星视线速度分布(LOSVD)中高速次级峰的原因。在这里,我们作出进一步的定性,但独特的预测的核盘的运动学特性,包括LOSVD在负的振幅(APOGEE-2将观察),并检查整个光盘的自行。由于核环也能够产生类似的高速LOSVD峰,我们提出了预测的自行签名区分核盘和核环。我们还证明,恒星在一个核盘,这将是x2轨道垂直于酒吧,可以保持在这些轨道上很长一段时间,因此可以是老的。我们表明,这样的(旧)核盘的可比大小存在于外部星系。
Discovery of the Distant, Ultra-Faint Milky Way Satellite Aquarius IV with the Vera C. Rubin Observatory Early Data Preview 2
Yale University(耶鲁大学);University of Chicago(芝加哥大学);Fermi National Accelerator Laboratory(费米国家加速器实验室);University of Virginia(弗吉尼亚大学);University of Washington(华盛顿大学)
A Deep Look at the Ultra-Faint Milky Way Satellite Virgo III with Rubin Observatory Data Preview 2
University of Chicago(芝加哥大学);Kavli Institute for Cosmological Physics, University of Chicago(芝加哥大学卡弗里宇宙物理学研究所);NSF-Simons AI Institute for the Sky (SkAI)(美国国家科学基金会-西蒙斯天空人工智能研究所);Fermi National Accelerator Laboratory(费米国家加速器实验室);Department of Astronomy and Astrophysics, University of Chicago(芝加哥大学天体物理学系);DIRAC Institute, Department of Astronomy, University of Washington(华盛顿大学天文学系迪拉克研究所);Department of Astronomy, Yale University(耶鲁大学天文学系)
Rubin Observatory Reveals a Dust-Shrouded Halo Globular Cluster in Ophiuchus
University of Chicago(芝加哥大学);Yale University(耶鲁大学);University of Virginia(弗吉尼亚大学);Fermi National Accelerator Laboratory(费米国家加速器实验室);University of Washington(华盛顿大学)
The Tenth Data Release of the Sloan Digital Sky Survey: First Spectroscopic Data from the SDSS-III Apache Point Observatory Galactic Evolution Experiment
Validation of the Bond et al. (2010) SDSS-derived kinematic models for the Milky Way's disk and halo stars with Gaia Data Release 3 proper motion and radial velocity data
本文利用 Gaia DR3 数据验证 Bond et al. (2010) 基于 SDSS 的银河系盘星与晕星运动学模型,证实其对盘星旋转速度偏态分布、垂直梯度及三分量速度弥散的预测准确,并确认晕星速度椭球在球坐标下的空间不变性。