We present the new technique for the determination of the low-mass slope of the stellar mass function from the pixel-space fitting of integrated light spectra. This technique is the extension of the NBursts full spectral fitting technique. It can be used to constrain the stellar initial mass function (IMF) of compact stellar systems having high relaxation timescales (Hubble time or more). We used Monte-Carlo simulations with mock spectra to test the technique and conclude that: (1) age, metallicity, and IMF can be very precisely determined in the first "unrestricted" variant of the code for high signal-to-noise datasets (S/N=100, R=7000 give the uncertainty of alpha of about 0.1); (2) adding the M/L information significantly improves the precision and reduces the degeneracies, however systematic errors in M/L will translate into offsets in the IMF slope.
paired: A Statistical Framework for Detecting Stellar Binarity with Gaia RVs. I. Sensitivity to Unresolved Binaries
University of Florida（佛罗里达大学）；Center for Computational Astrophysics, Flatiron Institute（纽约市立学院西蒙斯数据科学研究所计算天体物理中心）；School of Physics & Astronomy, Monash University（蒙纳士大学物理与天文学院）；Center of Excellence for Astrophysics in Three Dimensions (ASTRO-3D)（三维天体物理学卓越中心）
NBursts+phot: parametric recovery of galaxy star formation histories from the simultaneous fitting of spectra and broad-band spectral energy distributions
The Cannon: A data-driven approach to stellar label determination
新的光谱调查提供了一致的恒星参数和丰度（“恒星标签”）在银河系数十万颗恒星的承诺：这构成了一个艰巨的光谱建模挑战。在许多情况下，有一个参考天体的子集，其恒星标签是已知的高保真度。我们利用这一点与大炮，一个新的数据驱动的方法来确定恒星标签从光谱数据。Cannon通过在每个波长拟合一个灵活的模型，从参考星的“已知”标签中学习连续归一化光谱如何依赖于这些标签;然后，Cannon使用这个模型来推导剩余巡天星的标签。我们通过在19个星团中的542颗恒星上训练模型作为参考对象来说明大炮，Teff，log g和[Fe/H]作为标签，然后将其应用于APOGEE DR 10的56，000颗恒星的光谱。大炮非常准确。它的恒星标签与DR 10中提供的APOGEE管道（ASPCAP）标签的恒星相比很好，均方根差异基本上与所述的ASPCAP不确定度相同。除了参考标签，大炮没有使用恒星模型或任何线列表，但需要一组跨越标签空间的参考对象。Cannon在较低的信噪比下表现良好，因为即使在APOGEE观测时间的九分之一，它也能提供非常好的标签。我们讨论了大炮的局限性和未来的潜力，特别是，使不同的光谱调查到一个一致的规模的恒星标签。
