The star formation rate (SFR) of the Milky Way remains poorly known, with often-quoted values ranging from 1 to 10 M ☉?yr–1. This situation persists despite the potential for the Milky Way to serve as the ultimate SFR calibrator for external galaxies. We show that various estimates for the Galactic SFR are consistent with one another once they have been normalized to the same initial mass function (IMF) and massive star models, converging to 1.9 ± 0.4 M ☉?yr–1. However, standard SFR diagnostics are vulnerable to systematics founded in the use of indirect observational tracers sensitive only to high-mass stars. We find that absolute SFRs measured using resolved low/intermediate-mass stellar populations in Galactic H II regions are systematically higher by factors of ~2-3 compared with calibrations for SFRs measured from mid-IR and radio emission. We discuss some potential explanations for this discrepancy and conclude that it could be allayed if (1) the power-law slope of the IMF for intermediate-mass (1.5 M ☉ m 5M ☉)?stars were steeper than the Salpeter slope or (2) a correction factor was applied to the extragalactic 24 μm SFR calibrations to account for the duration of star formation in individual mid-IR-bright H II regions relative to the lifetimes of O?stars. Finally, we present some approaches for testing whether a Galactic SFR of ~2 M ☉?yr–1 is consistent with what we would measure if we could view the Milky Way as external observers. Using luminous radio supernova remnants and X-ray point sources, we find that the Milky Way deviates from expectations at the 1σ-3σ level, hinting that perhaps the Galactic SFR is overestimated or extragalactic SFRs need to be revised upward.
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机译：银河系的恒星形成率（SFR）仍然知之甚少，经常被引用的值范围是1到10 M yryr-1。尽管银河系有可能用作外部星系的终极SFR校准器，但这种情况仍然存在。我们显示，一旦将银河系SFR的各种估计值归一化为相同的初始质量函数（IMF）和大质量恒星模型（收敛至1.9±0.4 M yryr-1），则它们彼此一致。但是，标准SFR诊断很容易受到使用仅对高质量恒星敏感的间接观测示踪剂建立的系统学的影响。我们发现，与从中红外和无线电发射测得的SFR的标定值相比，使用银河H II地区中解析的低/中等质量恒星群测得的绝对SFR的系统值要高约2-3倍。我们讨论了对此差异的一些潜在解释，并得出结论，如果（1）IMF中等质量星（1.5 M☉展开▼
