Nature, 29 June 2023, Volume 618 Issue 7967

《天然》2023年6月29日，第618卷，7967期

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天文学Astronomy

A close-in giant planet escapes engulfment by its star

一颗逃走了被恒星吞没运气的近间隔巨行星

▲ 作者：Marc Hon, Daniel Huber, Nicholas Z. Rui et al.

▲ 链接：

https://www.nature.com/articles/s41586-023-06029-0

▲ 择要：

于此，咱们发明巨行星8 Ursae Minoris b缭绕一个焦点氦燃烧的红巨星扭转。这颗行星将于间隔它的主恒星只要0.5天文单元的间隔时被主恒星吞没，按照尺度的单星演化猜测，它的半径以前已经经扩展到0.7天文单元。

思量到燃烧氦的巨行星的寿命很短，且这颗行星的轨道近圆形，这与行星于最初远间隔环抱的环境纷歧致。相反，这颗行星可能经由过程恒星归并防止了被吞没。这类归并可能转变了主恒星的演化环境，或者使患上8 Ursae Minoris b成为第二代行星。

这一体系注解，焦点氦燃烧的红巨星可以包涵近地行星，同时也为非尺度恒星演化于晚期系生手星体系的保存中所起的作用提供了证据。

▲ Abstract：

Here we present the discovery that the giant planet 8 Ursae Minoris b orbits a core-helium-burning red giant. At a distance of only 0.5?AU from its host star, the planet would have been engulfed by its host star, which is predicted by standard single-star evolution to have previously expanded to a radius of 0.7?AU. Given the brief lifetime of helium-burning giants, the nearly circular orbit of the planet is challenging to reconcile with scenarios in which the planet survives by having a distant orbit initially. Instead, the planet may have avoided engulfment through a stellar merger that either altered the evolution of the host star or produced 8 Ursae Minoris b as a second-generation planet. This system shows that core-helium-burning red giants can harbour close planets and provides evidence for the role of non-canonical stellar evolution in the extended survival of late-stage exoplanetary systems.

物理学Physics

Magnetic-field-sensitive charge density waves in the superconductor UTe2

超导体UTe2中的磁场敏感电荷密度波

▲ 作者：Anuva Aishwarya, Julian May-Mann et al.

▲ 链接：

https://www.nature.com/articles/s41586-023-06005-8

▲ 择要：

于此，咱们使用扫描地道显微镜展现了重费米子三重态超导体UTe2中不平常的电荷密度波（CDW）挨次。咱们的高分辩率图展现了一个多份量不相当的CDW，其强度跟着场的增年夜而削弱，CDW终极于超导临界场Hc2下消散。

为了理解这类不平常的电荷密度波征象，咱们构建了一个基在Ginzburg-Landau理论的模子，该模子描写了匀称三重态超导体与三个三重态配对于密度波态的共存。该理论预示了一种因发源在三重态配对于密度波态、而对于磁场敏感的子电荷密度波。这类理论也为咱们的数据提供了可能的注释。

▲ Abstract：

Here we use scanning tunnelling microscopy to reveal an unusual charge-density-wave (CDW) order in the heavy-fermion triplet superconductor UTe2. Our high-resolution maps reveal a multi-component inco妹妹ensurate CDW whose intensity gets weaker with increasing field, with the CDW eventually disappearing at the superconducting critical field Hc2. To understand the phenomenology of this unusual CDW, we construct a Ginzburg–Landau theory for a uniform triplet superconductor coexisting with three triplet pair-density-wave states. This theory gives rise to daughter CDWs that would be sensitive to magnetic field owing to their origin in a pair-density-wave state and provides a possible explanation for our data.

化学Chemistry

Chiral phonons in quartz probed by X-rays

用X射线探测石英中的手性声子

▲ 作者：Hiroki Ueda, Mirian García-Fernández et al.

▲ 链接：

https://www.nature.com/articles/s41586-023-06016-5

▲ 择要：

于此，咱们的试验证实了用圆偏振x射线的共振非弹性X射线散射可展示了手性声子。哄骗典型的手性质料石英，咱们证实了固有手性的圆偏振X射线于倒易空间的特定位置与手性声子耦合，使患上咱们能确定晶格模式的手性色散。

咱们敌手性声子的试验证实证实了凝结态物资的一种新自由，即很是主要，又为摸索基在手性博色子的新征象打开了年夜门。

▲ Abstract：

Here we show experimental proof of chiral phonons using resonant inelastic X-ray scattering with circularly polarized X-rays. Using the prototypical chiral material quartz, we demonstrate that circularly polarized X-rays, which are intrinsically chiral, couple to chiral phonons at specific positions in reciprocal space, allowing us to determine the chiral dispersion of the lattice modes. Our experimental proof of chiral phonons demonstrates a new degree of freedom in condensed matter that is both of fundamental importance and opens the door to exploration of new emergent phenomena based on chiral bosons.

年夜气科学Atmospheric Sciences

Natural short-lived halogens exert an indirect cooling effect on climate

自然的短命命卤素对于天气有直接的降温作用

▲ 作者：Alf����APPonso Saiz-Lopez, Rafael P. Fernandez et al.

▲ 链接：

https://www.nature.com/articles/s41586-023-06119-z

▲ 择要：

于此，咱们展示了短命命卤素对于臭氧的辐射扰动（- 0.24±0.02瓦/平方米）孕育发生了本色性的直接冷却效应（- 0.13±0.03瓦/平方米），由甲烷（+0.09±0.01瓦/平方米）、气溶胶（+0.03±0.01瓦/平方米）以及平流层水蒸气（+0.011±0.001瓦/平方米）的辐射扰动赔偿（+0.011±0.001瓦/平方米）。

主要的是，自1750年以来，因为天然卤素排放的报酬增长，这类本色性的冷却效应上升了- 0.05±0.03瓦/平方米（61%），按照天气变暖猜测以及社会经济成长，估计将来将进一步变迁（到2100年为18 - 31%）。咱们总结到，短命命卤素因为直接辐射效应，应该纳入天气模子，以提供一个更实际的地球天气体系的天然基线。

▲ Abstract：

Here we show that short-lived halogens exert a substantial indirect cooling effect at present (?0.13?±?0.03?watts per square metre) that arises from halogen-mediated radiative perturbations of ozone (?0.24?±?0.02?watts per square metre), compensated by those from methane (+0.09?±?0.01?watts per square metre), aerosols (+0.03?±?0.01?watts per square metre) and stratospheric water vapour (+0.011?±?0.001?watts per square metre). Importantly, this substantial cooling effect has increased since 1750 by ?0.05?±?0.03?watts per square metre (61?per cent), driven by the anthropogenic amplification of natural halogen emissions, and is projected to change further (18–31?per cent by 2100) depending on climate warming projections and socioeconomic development. We conclude that the indirect radiative effect due to short-lived halogens should now be incorporated into climate models to provide a more realistic natural baseline of Earth’s climate system.

地舆学Geography

Uncovering the Ediacaran phosphorus cycle

揭秘埃迪卡拉纪磷轮回

▲ 作者：Matthew S. Dodd, Wei Shi, Chao Li et al.

▲ 链接：

https://www.nature.com/articles/s41586-023-06077-6

▲ 择要：

于此，咱们使用来自全世界漫衍的六个剖面的碳酸盐岩相干磷酸盐技能（CAP），重修与全世界海洋氧合配合发生的年夜范围负碳同位素漂移Shuram漂移（SE）时期的海洋磷浓度。咱们的研究数据注解，于Shuram漂移降落以及上升时期，海洋磷浓度呈脉冲增加。

经由过程定量的生物地球化学模子，咱们提出这一征象可以注释为重要由硫酸盐氧化的海洋无机物开释二氧化碳以及磷，和二氧化碳驱动的陆地风化进一步开释磷。总的来讲，这可能致使无机黄铁矿埋藏以及海洋氧化作用的增长。咱们的CAP数据好像也注解，于Shuram漂移沿海的最年夜以及最小水平的海洋缺氧前提下，海洋磷浓度是相称的。

▲ Abstract：

Here we use carbonate-associated phosphate (CAP) from six globally distributed sections to reconstruct oceanic phosphorus concentrations during a large negative carbon-isotope excursion—the Shuram excursion (SE)—which co-occurred with global oceanic oxygenation. Our data suggest pulsed increases in oceanic phosphorus concentrations during the falling and rising limbs of the SE. Using a quantitative biogeochemical model, we propose that this observation could be explained by carbon dioxide and phosphorus release from marine organic-matter oxidation primarily by sulfate, with further phosphorus release from carbon-dioxide-driven weathering on land. Collectively, this may have resulted in elevated organic-pyrite burial and ocean oxygenation. Our CAP data also seem to suggest equivalent oceanic phosphorus concentrations under maximum and minimum extents of ocean anoxia across the SE.

Microbial carbon use efficiency promotes global soil carbon storage

微生物碳哄骗效率提高全世界泥土碳储量

▲ 作者：Feng Tao, Yuanyuan Huang et al.

▲ 链接：

https://www.nature.com/articles/s41586-023-06042-3

▲ 择要：

于此，咱们接纳全世界标准数据集、微生物历程显式模子、数据夹杂、深度进修以及元阐发相联合的要领，研究了微生物碳哄骗效率（CUE）与泥土无机碳生存之间的瓜葛，和与天气、植被以及泥土性子的彼此作用。咱们发明，于决议全世界碳储量及其空间变迁方面，CUE的主要性至少是其他评估要素（如碳输入、分化或者垂直运输）的4倍。

CUE与泥土无机碳含量呈显著正相干。咱们的研究成果注解，CUE是全世界泥土无机碳贮存的重要决议要素。相识CUE暗地里的微生物历程及其对于情况的依靠性，有助在猜测泥土无机碳对于天气变迁的反馈。

▲ Abstract：

Here we examine the relationship between CUE and the preservation of SOC, and interactions with climate, vegetation and edaphic properties, using a combination of global-scale datasets, a microbial-process explicit model, data assimilation, deep learning and meta-analysis. We find that CUE is at least four times as important as other evaluated factors, such as carbon input, decomposition or vertical transport, in determining SOC storage and its spatial variation across the globe. In addition, CUE shows a positive correlation with SOC content. Our findings point to microbial CUE as a major determinant of global SOC storage. Understanding the microbial processes underlying CUE and their environmental dependence may help the prediction of SOC feedback to a changing climate.

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