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2511.04733 2026-06-10 astro-ph.CO

Combining CMB datasets with consistent foreground modelling

结合CMB数据集与一致的前景建模

M. Tristram, M. Douspis, A. Gorce, S. Henrot-Versillé, L. T. Hergt, S. Ilic, L. McBride, M. Muñoz-Echeverría, E. Pointecouteau, L. Salvati

AI总结 本文通过联合分析普朗克卫星、阿塔卡马宇宙望远镜和南极望远镜的数据,构建统一的似然函数以建模CMB信号及前景,展示前景建模一致性对参数估计的重要性。

Comments 12 pages, 17 figures, 5 appendix pages. accepted in A&A

详情
Journal ref
A&A 710, A165 (2026)
AI中文摘要

我们提出了一个联合宇宙学分析,结合普朗克卫星、阿塔卡马宇宙望远镜和南极望远镜的数据。我们构建了一个统一的似然函数,通过联合建模宇宙微波背景(CMB)信号、银河系和 extragalactic 前景以及所有数据集的仪器系统误差,以重现测量的温度和偏振功率谱。我们通过结合数据集来减少依赖性,并通过边缘化前景模板的选择来提高参数估计的鲁棒性。在这一联合分析中,ΛCDM参数对前景建模的变化表现出显著的稳定性。宇宙学扩展参数对这些假设更为敏感,边缘化前景模型后,中微子领域不确定性增加高达35%。相比之下,前景参数的确定更强烈依赖于对底层前景模型假设的设定。总体而言,这项工作展示了当前CMB实验完全联合分析的可行性和可靠性,并强调了在下一代高灵敏度CMB调查的科学目标中,一致和准确的前景建模的重要性。

英文摘要

We present a joint cosmological analysis combining data from the Planck satellite, the Atacama Cosmology Telescope, and the South Pole Telescope. We construct a unified likelihood that reproduces the measured temperature and polarisation power spectra by jointly modelling the cosmic microwave background (CMB) signal, Galactic and extragalactic foregrounds, and instrumental systematics across all datasets. We reduce reliance by combining datasets and improve the robustness of parameter estimation by marginalising over the choice of foreground templates. Within this joint analysis, $Λ$CDM parameters exhibit remarkable stability with respect to variations in foreground modelling. Parameters for cosmological extensions are more sensitive to these assumptions, with uncertainties increasing by up to 35% in the neutrino sector after marginalising over foreground models. In contrast, the determination of foreground parameters depends more strongly on the assumptions made about the underlying foreground models. Overall, this work demonstrates the feasibility and reliability of a fully joint analysis of current CMB experiments and emphasizes the importance of consistent and accurate foreground modelling for the scientific goals of next-generation, high-sensitivity CMB surveys.

2309.04231 2026-06-10 hep-th

Subregion Complementarity in AdS/CFT

AdS/CFT中子区域互补性

Sotaro Sugishita, Seiji Terashima

AI总结 研究AdS/CFT对应中子区域双重视觉,指出在大N极限下,因果楔重建与全局重建存在差异,提出子区域互补性,说明不同CFT算符可描述bulk子区域,但不适用于单侧黑洞。

Comments 42 pages, 5 figure, v2: includes corrections to discussion on subregion complementarity, minor corrections, v3: clarification added

详情
Journal ref
Prog Theor Exp Phys (2026)
AI中文摘要

我们研究AdS/CFT对应中的bulk重建。我们证明子区域双重视觉不成立,突出在大N极限下,因果楔重建与全局重建之间的差异。我们论证基于全息量子误差纠正码的entanglement wedge重建无效,归因于非微扰有限N效应或因视界附近trans-Planckian模式引起的量子引力效应。然而,我们提出子区域互补性,说明不同CFT算符可描述bulk子区域。尽管我们预期这种互补性在一般永恒黑洞外视界外有效,但在单侧黑洞中不适用,因为缺乏在拉伸视界处的半经典描述。

英文摘要

We examine the bulk reconstruction in the AdS/CFT correspondence. We demonstrate that the subregion duality fails to hold, highlighting discrepancies between operators in causal wedge reconstruction and those in global reconstruction at the leading order in the large $N$ limit. We argue the invalidity of the entanglement wedge reconstruction based on the holographic quantum error correction code, attributing it to non-perturbative finite $N$ effects or quantum gravity effects due to the trans-Planckian modes near the horizon. Nevertheless, we propose the subregion complementarity, illustrating that different CFT operators can describe a bulk subregion. While we expect that this complementarity is valid outside the horizon in general eternal black holes, it is inapplicable for single-sided black holes where a semi-classical description at the stretched horizon is absent.

2507.02605 2026-06-10 hep-th hep-ph

Trans-series from condensates in the non-linear sigma model

从非线性σ模型中的凝聚态获得转系列

Yizhuang Liu, Marcos Mariño

AI总结 本文提出一个无质量的微扰框架,用于二维非线性σ模型,用于计算算子乘积展开中算子凝聚态的微扰级数。该框架基于四次线性σ模型的极限,且显式保持O(N)对称性,并在1/N展开的次主导项中重现了两点函数的微扰贡献及其因拉格朗日算子凝聚态产生的指数小修正。

Comments 40 pages, 8 figures; v2: reorganized sections for improved clarity of exposition. Minor corrections and clarifications added. Results unchanged

详情
Journal ref
SciPost Phys. 20, 156 (2026)
AI中文摘要

在本文中,我们为二维非线性σ模型(NLSM)提供了一个无质量的微扰框架,该框架允许计算与算子乘积展开(OPE)中算子凝聚态相关的微扰级数。该框架基于四次线性σ模型(LSM)的极限,并显式保持O(N)对称性。我们展示,在1/N展开的次主导项中,该框架如何重现两点函数的微扰贡献,以及其因拉格朗日算子凝聚态产生的第一个指数小修正,完全符合非微扰的大N解。我们还展示,在完整的LSM中,自然紫外截断处的物理确实与NLSM在红外区域分离,特别是在弱耦合极限下。特别是,我们展示在截断尺度下LSM的微扰框架与NLSM的微扰框架相连接。LSM正则化中幂发散的结构还表明,NLSM微扰自能的正Borel轴上的第一个重整子是紫外重整子,它抵消了凝聚态中的不确定性。

英文摘要

In this work we provide a massless perturbative framework for the two dimensional non-linear sigma model (NLSM), that allows the computation of the perturbative series attached to the operator condensates in the operator product expansion (OPE). It is based on a limit of the quartic linear sigma model (LSM) and is manifestly $O(N)$ symmetric. We show, at next-to-leading order in the $1/N$ expansion, how this framework reproduces the perturbative contribution to the two-point function, as well as its first exponentially small correction due to the condensate of the Lagrangian operator, in full agreement with the exact non-perturbative large $N$ solution. We also show that, in the full LSM, the physics at the natural UV cutoff indeed decouples from the NLSM in the IR, in the weak-coupling limit. In particular, we show that the perturbative framework for the LSM at the cutoff scale is connected to the one in the NLSM. The structure of power divergences in the LSM regularization also reveals that the first renormalon on the positive Borel axis of the NLSM perturbative self-energy is an UV renormalon, which cancels against the ambiguity in the condensate.

2604.18382 2026-06-10 astro-ph.GA

Molecular Clouds at the Edge of the Galaxy II. Physical properties and scaling relations

银河边缘的分子云 II. 物理性质和标度关系

C. S. Luo, X. D. Tang, C. Henkel, Y. Sun, Y. Gong, X. W. Zheng, T. Liu, X. Lu, Y. P. Ao, X. P. Chen, D. L. Li, Y. X. He, K. Wang, J. W. Wu, J. Esimbek, J. J. Zhou, G. Wu, Y. X. Ma, W. A. Baan, J. J. Qiu, X. Zhao, J. S. Li, Q. Zhao, L. D. Liu, C. Y. Wang

AI总结 研究银河边缘分子云的物理性质和标度关系,通过CO(2-1)线观测发现云团参数在不同银河系心距范围内无系统变化,揭示了湍流和光度质量-大小关系。

详情
Journal ref
A&A 710, A137 (2026)
AI中文摘要

银河边缘提供了一个研究低金属licity环境下分子云和恒星形成的理想场所。利用IRAM 30 m望远镜的CO(2-1)线观测,共发现了72个银河边缘云团,识别出112个CO云团,线性分辨率为0.5-0.9 pc。这些云团的大小、质量、表面密度和速度分散率范围分别为0.6-3.4 pc,34-8250 M_sun,12-1025 M_sun pc^{-2},和0.3-1.7 km s^{-1}。在14-23 kpc的银河系心距范围内,这些参数无系统变化。银河边缘云团的速度分散率与有效半径的关系模型为σ_v = 0.69(±0.03) R_eff^{0.36(±0.10)},表明银河边缘云团中存在湍流,类似于银河内盘云的观测结果。此外,银河边缘云团的光度质量-大小关系为M_lum = 196(±17) R_eff^{2.18(±0.26)},表明不同大小云团的平均柱密度几乎恒定。束缚参数范围为0.6-15.3,中位数为2.8 ± 0.6,表明大多数云团未被引力束缚。此外,银河边缘云团的束缚参数随着银河系心距的增加呈指数下降趋势,描述为α_vir = 33.0(±10.4) e^{-R_g/6.7(±0.9)},与先前结果一致。

英文摘要

The outer Galaxy presents an optimal setting for investigating molecular clouds and star formation in environments with low metallicity. A total of 72 Galactic edge clouds were surveyed using the CO\,(2--1) line with the IRAM\,30\,m telescope, leading to the identification of 112 CO clumps within molecular clouds with linear resolutions of 0.5--0.9\,pc. Parameters such as size, mass, surface density, and velocity dispersion of these CO clumps, derived from CO\,(2--1) observations, exhibit ranges of 0.6--3.4\,pc, 34--8250\,M$_\odot$, 12--1025\,M$_{\odot}$\,pc$^{-2}$, and 0.3--1.7\,km\,s$^{-1}$, respectively. Over the Galactocentric distance range of 14--23\,kpc, no systematic variations are found in these parameters. The velocity dispersion-size relationship of the Galactic edge clumps is modeled as $σ_{\rm v}$\,=\,0.69($\pm$0.03)$R_{\rm eff}^{0.36(\pm0.10)}$, indicating that turbulence is present within the Galactic edge clumps, akin to observations in the inner Galactic disk clouds. Furthermore, the luminous mass-size relation of the Galactic edge clumps is described by $M_{\rm lum}$\,=\,196($\pm$17)$R_{\rm eff}^{\,2.18\,(\pm0.26)}$, suggesting the average column density remains almost constant for clouds of different sizes. The virial parameters range from 0.6 to 15.3, with a median value of 2.8\,$\pm$\,0.6, suggesting that most clumps are gravitationally unbound. Furthermore, the virial parameters of our Galactic edge clumps show a decreasing trend with increasing Galactocentric distances, described by an exponential relation $α_{\rm vir}$\,=\,33.0($\pm$\,10.4)\,e$^{-R_{\rm g}/6.7(\pm0.9)}$, consistent with previous results.

2401.11752 2026-06-10 cs.LO math.CT

Univalent Enriched Categories and the Enriched Rezk Completion

单值富范畴与富Rezk完备化

Niels van der Weide

AI总结 本文研究单值富范畴,证明本质满且全忠实函子等价,并构造富范畴的Rezk完备化,进而用于构造单值富Kleisli范畴。

详情
Journal ref
Logical Methods in Computer Science, Volume 22, Issue 2 (June 2, 2026) lmcs:15947
AI中文摘要

富范畴是其态射集具有额外结构的范畴。这类范畴在高阶范畴、同伦论和编程语言语义学中扮演重要角色。本文研究单值富范畴。我们证明单值富范畴之间的所有本质满且全忠实函子都是等价,并证明每个富范畴都允许Rezk完备化。最后,我们利用富范畴的Rezk完备化构造单值富Kleisli范畴。

英文摘要

Enriched categories are categories whose sets of morphisms are enriched with extra structure. Such categories play a prominent role in the study of higher categories, homotopy theory, and the semantics of programming languages. In this paper, we study univalent enriched categories. We prove that all essentially surjective and fully faithful functors between univalent enriched categories are equivalences, and we show that every enriched category admits a Rezk completion. Finally, we use the Rezk completion for enriched categories to construct univalent enriched Kleisli categories.

2604.16650 2026-06-10 astro-ph.HE astro-ph.SR gr-qc

Neutron star atmospheres composed of fusion ashes

中子星大气层由核聚变残渣组成

Valery F. Suleimanov, Juri Poutanen, Klaus Werner

AI总结 本文研究了由不同化学成分热核残渣构成的中子星大气模型,探讨了核燃烧残渣对X射线爆发中子星表面的影响,分析了辐射压力对最大光度的限制及吸收边的能量特征。

Comments 16 pages, 21 figures, 6 tables, accepted to A&A, reference to Zenodo, where all the spectra and their fitting parameters are presented

详情
Journal ref
A&A 710, A169 (2026)
AI中文摘要

本文提出了由不同化学成分热核残渣构成的中子星高温大气模型。这些模型对于研究X射线爆发中子星中的热核闪光至关重要,其中核燃烧残渣被输送到恒星表面。我们考虑了四种不同的混合物,分别由氦、铬、铁和镍主导。除了之前用于中子星大气建模中已使用的不透明源外,我们还加入了由激发离子态产生的光电离以及大约5000条光谱线。我们还开发了一种方法,能够同时处理康普顿散射和大量光谱线。所建模的中子星大气层的一个关键特征是在光学薄和光学厚大气部分之间的过渡区域中存在一层,其中辐射压力力显著增加。这种增强的力对给定的表面重力和化学组成下的最大可获得的光度设置了一个上限。计算出的大气层的发射光谱显示出明显的吸收边,其能量由主导的化学物种决定。我们使用稀释黑体修改后加入单个吸收边来拟合模型光谱,并研究了拟合参数如何依赖于相对光度和大气的化学组成。最后,我们讨论了这些模型受到X射线爆发中出现吸收边的系统(如HETE~J1900.1$-$2455和GRS~1747$-$312)的性质的限制。

英文摘要

Here we present models of hot neutron star (NS) atmospheres consisting of thermonuclear ashes of various chemical compositions. These models are essential for studying thermonuclear flashes in X-ray bursting NSs in which nuclear-burning ashes are transported to the stellar surface. We consider four different mixtures, each dominated by helium, chromium, iron, or nickel. In addition to the opacity sources previously used in NS atmosphere modeling, we include photoionization from excited ionic states as well as approximately 5000 spectral lines. We also develop a method that enables the simultaneous treatment of Compton scattering and a large number of spectral lines. A key feature of the modeled NS atmospheres is the presence of a layer in the transition region between the optically thin and optically thick parts of the atmosphere where the radiation-pressure force increases significantly. This enhanced force sets an upper limit on the maximum attainable bolometric flux for a given surface gravity and chemical composition. The emergent spectra from the computed atmospheres display pronounced absorption edges, whose energies are determined by the dominant chemical species. We fit the model spectra using a diluted blackbody modified by a single absorption edge, and we investigate how the fit parameters depend on both the relative bolometric flux and the chemical composition of the atmosphere. Finally, we discuss constraints on these models imposed by the properties of X-ray bursts that exhibit absorption edges in their spectra, as observed in the systems HETE~J1900.1$-$2455 and GRS~1747$-$312.

2511.14572 2026-06-10 astro-ph.CO

Forecasting synchrotron spectral parameters with QUIJOTE-MFI2 in combination with Planck and WMAP

利用QUIJOTE-MFI2与普朗克和威姆萨斯数据预测同步辐射光谱参数

Ana Almeida, José Alberto Rubiño-Martín, Roke Cepeda-Arroita, Ricardo Tanausú Génova-Santos, Debabrata Adak

AI总结 本文通过模拟天空地图展示QUIJOTE-MFI2在10-20GHz频段对极化同步辐射发射的约束效果,证明其能显著降低参数不确定性,尤其在极化幅度方面提升显著。

Comments 19 pages, 16 figures, 4 tables, accepted for publication to A&A

详情
Journal ref
A&A 710, A110 (2026)
AI中文摘要

我们提出了QUIJOTE-MFI2仪器(10-20GHz)的参数分离预测,评估其对1度FWHM和N_side=64下极化同步辐射发射的约束影响。基于幂律和弯曲同步辐射光谱的模拟天空地图,我们显示将QUIJOTE-MFI2与现有WMAP+Planck+MFI数据结合,可获得统计无偏的参数估计,同时显著降低不确定性:同步辐射光谱指数(β_s)的改进因子达约10,曲率参数(C_s)达约5,极化幅度在明亮区域达约43。深QUIJOTE宇宙场使β_s约束在固有低信噪比区域也有效,即使WMAP+Planck单独仍受先验主导。当前综合灵敏度不足以在像素级检测C_s=-0.052的同步辐射曲率,但可在银河系平面最亮区域检测C_s≈0.14的2σ水平。在这些深宇宙场中,将QUIJOTE-MFI2与WMAP和Planck结合,使100GHz处同步辐射残差中位数降低到0.033μK_CMB。这些结果表明QUIJOTE-MFI2将为建模银河同步辐射提供关键低频信息,为未来CMB调查如LiteBIRD和Simons Observatory提供有价值的补充约束。

英文摘要

We present a parametric component separation forecast for the QUIJOTE-MFI2 instrument (10-20 GHz), assessing its impact on constraining polarised synchrotron emission at $1^\circ$ FWHM and $N_{\rm side}=64$. Using simulated sky maps based on power-law and curved synchrotron spectra, we show that adding QUIJOTE-MFI2 to existing WMAP+$Planck$+MFI data yields statistically unbiased parameter estimates with substantial uncertainty reductions: improvement factors reach $\sim$10 for the synchrotron spectral index ($β_s$), $\sim$5 for the curvature parameter ($C_s$), and $\sim$43 for polarisation amplitudes in bright regions. Deep QUIJOTE cosmological fields enable $β_s$ constraints even in intrinsically low SNR regions where WMAP+$Planck$ alone remain prior-dominated. Current combined sensitivities are insufficient to detect a synchrotron curvature of $C_s=-0.052$ on a pixel-by-pixel basis, but a $2σ$ detection is achievable for $|C_s|\gtrsim 0.14$ in the brightest regions of the Galactic plane. In those deep cosmological fields, combining QUIJOTE-MFI2 with WMAP and $Planck$ reduces the median synchrotron residual at 100 GHz by a factor of 6, to 0.033 $μ$K$_{\rm CMB}$. These results demonstrate that QUIJOTE-MFI2 will provide critical low-frequency information for modelling Galactic synchrotron emission, offering valuable complementary constraints for future CMB surveys such as LiteBIRD and the Simons Observatory.

2604.15519 2026-06-10 q-fin.ST

Broken Symmetry, Conservation Law, and Scaling in Accumulated Stock Returns -- a Modified Jones-Faddy Skew t-Distribution Perspective

对称性破缺、守恒定律与积累股票收益的缩放——一种修改后的Jones-Faddy偏斜t分布视角

Arshia Ghasemi, Siqi Shao, R. A. Serota

AI总结 研究分析S&P500多日收益的对称性破缺及波动率与积累天数的线性关系,采用修改后的Jones-Faddy偏斜t分布进行分析。

Comments 26 pages, 24 figures, 4 tables

详情
Journal ref
Foundations 2026, 6(2), 23
AI中文摘要

我们分析了S&P500历史多日收益:从每日收益到最多十日累计收益。尽管收益分布中收益与损失的对称性破缺导致其正均值和负偏斜,但实际波动率(方差)表现出与积累天数显著的线性关系。均值也显示出几乎完美的线性关系。我们使用修改后的Jones-Faddy偏斜t分布,从分析和数值两个方面分析这一现象。

英文摘要

We analyze historic S&P500 multi-day returns: from daily returns to those accumulated over up to ten days. Despite symmetry breaking between gains and losses in the distribution of returns, resulting in its positive mean and negative skew, realized variance (volatility squared) exhibits remarkably good linear dependence on the number of days of accumulation. Mean of the distribution also shows near perfect linear dependence as well. We analyze this phenomenon both analytically and numerically using a modified Jones-Faddy skew t-distribution.

2604.14819 2026-06-10 astro-ph.SR astro-ph.HE

Numerical investigation of particle acceleration at interplanetary shocks: diffusive and superdiffusive scenarios

行星际激波中粒子加速的数值研究:扩散与超扩散情景

Giuseppe Prete, Gaetano Zimbardo, Silvia Perri

AI总结 本文通过数值模拟研究行星际激波中粒子加速机制,采用扩散和超扩散模型,结合Fermi型加速机制和Langevin方程,验证了超扩散对粒子加速过程的加速作用及与观测一致的能量分布。

Comments The Article has been accepted in A&A

详情
Journal ref
A&A 710, A114 (2026)
AI中文摘要

高能粒子在空间和天体物理等离子体中普遍存在,行星际激波被认为是太阳系中主要的粒子加速器之一。现场测量通常显示高能粒子通量在激波处峰值,表明局部加速过程。此外,高能粒子通量的时间特性高度受激波上游和下游粒子输运特性影响。本文在先前的数值测试粒子模型基础上,加入了通过每次激波穿越时的能量增益加速粒子的机制,即一级Fermi型机制。此外,通过在无限平面激波上游和下游整合Langevin型方程,重现了70 keV粒子群体(即种子群体)的加速过程。粒子可通过随机“踢”在模拟框内扩散,这些“踢”属于高斯分布(正常扩散)或Levy分布(超扩散)。通过改变模型参数进行多次模拟,发现扩散和超扩散模拟中的粒子能谱与理论预测高度一致。输出的高能粒子密度与ACE航天器在2006年12月14日行星际激波穿越期间观测到的密度进行了比较。不仅显示不同能量bin的粒子通量在超扩散作用下能很好地再现观测到的上游和下游通量,还表明异常的超扩散输运加速了加速过程,并导致与观测一致的粒子能量值。

英文摘要

Energetic particles are ubiquitous in space and astrophysical plasmas, and interplanetary shocks are widely regarded as one of the main particle accelerators in the heliosphere. Indeed, in-situ measurements typically show that energetic particle fluxes peak at the shock, indicating a local acceleration process. Furthermore, the time profile of energetic particle fluxes is highly influenced by particle transport properties upstream and downstream of the shock. By advancing previous numerical test-particle models that simulate the transport of monoenergetic particles around an infinite planar shock, in this work we add the acceleration of such particles via energy gains at each shock crossing, in a first-order Fermi-type mechanism. Moreover, the acceleration of a 70 keV particle population, namely the seed population, is reproduced by integrating a Langevin-type equation upstream and downstream of an infinite planar shock. Particles can diffuse in the simulation box via random "kicks", which belong either to a Gaussian distribution (normal diffusion) or to a Levy distribution (superdiffusion). We perform several simulations by varying the parameters of the model. The particle energy spectra in both diffusive and superdiffusive simulations are in remarkable agreement with the theoretical predictions.The output energetic particle densities have been compared with those observed by the ACE spacecraft during an interplanetary shock crossing on December 14, 2006. We show not only that particle fluxes in different energy bins reproduce very well the observed ones upstream and downstream when superdiffusion is at work, but also that anomalous, superdiffusive transport speeds up the acceleration process and leads to values of particle energies consistent with observations.

2601.02555 2026-06-10 cond-mat.str-el

Influence of controlled disorder on the dipolar spin ice state of Ho-based pyrochlores

受受控杂乱性对Ho基磷酸盐的偶极子自旋冰态影响

A. A. Aczel, B. R. Ortiz, Y. Luo, G. Pokharel, P. M. Sarte, C. dela Cruz, J. Liu, G. Sala, S. D. Wilson, B. A. Frandsen, J. A. M. Paddison

AI总结 研究通过引入非磁性B位的位点混合,探讨了受控化学杂乱性对Ho基磷酸盐中偶极子自旋冰态的影响,发现杂乱性导致关联长度减小和局部结构畸变增加,但两者仍保持偶极子自旋冰态特征。

Comments 15 pages, 6 figures

详情
Journal ref
Phys. Rev. B 113, 214415 (2026)
AI中文摘要

形式为R₂B₂O₇的磷酸盐磁体,其中稀土离子在R位形成三维角共享四面体网络,为几何摩擦提供了经典设置。Ho基磷酸盐宿主偶极子自旋-冰基态,其特征是Ising时刻受冰规则约束,且具有类似于磁单极子的基本激发。本文研究了通过在非磁性B位引入位点混合来影响该状态的受控化学杂乱性,在两种化合物中。Ho₂GaSbO₇仅包含Ga³+/Sb⁵+电荷杂乱性,而Ho₂ScSbO₇则表现出电荷和显著的尺寸杂乱性,由于Sc³+和Sb⁵+的离子半径差异较大。尽管两种材料保持了磷酸盐结构,中子散射测量显示Ho₂ScSbO₇的R/B位阳离子有序的关联长度减小和局部结构畸变增强。尽管存在这些结构差异,总体热力学测量和磁性扩散散射显示两者都表现出偶极子自旋-冰态的特征。低能非弹性中子光谱进一步揭示了在偶极子自旋-冰区域内发展出的广谱磁激发,这是纯Ho磷酸盐中不存在的特征,表明杂乱性诱导了非克拉斯-基态双态的分裂。这些结果表明,受控杂乱性在Ho基磷酸盐中产生了可调的横向场驱动量子涨落,尽管偶极子自旋-冰态对这种杂乱性表现出异常的鲁棒性。

英文摘要

Pyrochlore magnets of the form $R_2B_2$O$_7$, in which rare-earth ions on the $R$-site form a three-dimensional network of corner-sharing tetrahedra, provide a canonical setting for geometrical frustration. Ho-based pyrochlores host a dipolar spin-ice ground state, characterized by Ising moments constrained by the ice rules and elementary excitations analogous to magnetic monopoles. Here we examine how controlled chemical disorder influences this state by introducing site mixing on the non-magnetic $B$-site in two compounds. Ho$_2$GaSbO$_7$ contains only Ga$^{3+}$/Sb$^{5+}$ charge disorder, whereas Ho$_2$ScSbO$_7$ exhibits both charge and substantial size disorder arising from the large ionic-radius mismatch between Sc$^{3+}$ and Sb$^{5+}$. Although both materials retain the pyrochlore structure, neutron scattering measurements reveal a reduced correlation length for the $R/B$-site cation ordering and enhanced local structural distortions in Ho$_2$ScSbO$_7$. Despite these structural differences, bulk thermodynamic measurements and magnetic diffuse scattering demonstrate that both systems exhibit the defining signatures of a dipolar spin-ice state. Low-energy inelastic neutron spectroscopy further uncovers broad magnetic excitations that develop within the dipolar spin-ice regime, a feature absent in pristine Ho pyrochlores and indicative of disorder-induced splitting of the non-Kramers ground-state doublet. Together, these results show that controlled disorder generates tunable transverse-field-driven quantum fluctuations in Ho-based pyrochlores, although the dipolar spin-ice state is remarkably robust to this disorder.

2510.02661 2026-06-10 cond-mat.mes-hall

Quantum geometric map of magnetotransport

磁输运的量子几何图谱

Longjun Xiang, Jinxiong Jia, Fuming Xu, Jian Wang

AI总结 本文提出量子几何图谱解释磁输运现象,揭示自旋和轨道诱导的霍尔效应由量子度量偶极和四极贡献,发现反常的间带贡献,研究拓扑绝缘体表面狄拉克锥的自旋诱导霍尔效应,发现阶梯状霍尔效应。

Comments Compared to the old version, this updated version has undergone significant changes to more clearly state the key results. In addition, the Onsager reciprocal relation on EB current response is added

详情
Journal ref
Phys. Rev. B 113, L201406 (2026)
AI中文摘要

我们提出一种量子几何图谱,用于解释磁非线性霍尔效应(MNHE)、平面霍尔效应(PHE)和普通霍尔效应(OHE)。这些磁输运现象源于电磁场中布洛赫电子的二阶电荷电流,结合自旋泽曼耦合和轨道最小耦合。基于昂萨格互易性,我们证明自旋和轨道诱导的MNHE由时间反演偶的泽曼量子度量偶极和常规量子度量四极主导;自旋和轨道诱导的PHE由时间反演奇的泽曼伯瑞曲率偶极和常规伯瑞曲率四极主导。我们进一步表明OHE包含与量子度量四极相关的间带贡献,与传统观点相悖。通过此图谱,我们研究了拓扑绝缘体表面狄拉克锥中未探索的自旋诱导PHE,发现阶梯状PHE。本文为理解磁输运实验提供了统一的量子几何框架。

英文摘要

We propose a quantum geometric map for the magnetononlinear Hall effect (MNHE), the planar Hall effect (PHE), and the ordinary Hall effect (OHE). These magnetotransport phenomena originate from the bilinear charge current of Bloch electrons in electromagnetic fields, incorporating both spin Zeeman coupling and orbital minimal coupling to the applied magnetic field. Benchmarked against Onsager reciprocity, we demonstrate that the spin- and orbital-induced MNHEs are governed by the time-reversal-even Zeeman quantum metric dipole and conventional quantum metric quadrupole, respectively; the spin- and orbital-induced PHEs are dominated by the time-reversal-odd Zeeman Berry curvature dipole and conventional Berry curvature quadrupole, respectively. We further show that the OHE contains an interband contribution that is related to the quantum metric quadrupole, contrary to conventional wisdom. Navigated by this map, we study the previously unexplored spin-induced PHE in the surface Dirac cone of topological insulators, where we uncover a step-like PHE. Our work offers a unified quantum geometric framework for understanding magnetotransport experiments.

2406.19206 2026-06-10 quant-ph cond-mat.mes-hall cond-mat.stat-mech

Quantum Thermodynamics

量子热力学

Patrick P. Potts

AI总结 本文探讨了量子系统中热、功和温度概念的延伸,介绍了小量子系统的热力学,并讨论了开放量子系统与热力学定律的关系。

Comments Submission to SciPost Phys. Lect. Notes

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Journal ref
SciPost Phys. Lect. Notes 126 (2026)
AI中文摘要

量子热力学理论研究了热、功和温度概念在量子领域的应用,展示了热力学定律如何从量子理论中推导出来,并介绍了如何用马尔可夫主方程建模开放量子系统。文章还讨论了设计用于冷却或生成纠缠的量子系统以及波动对热力学描述的影响。

英文摘要

The theory of quantum thermodynamics investigates how the concepts of heat, work, and temperature can be carried over to the quantum realm, where fluctuations and randomness are fundamentally unavoidable. These lecture notes provide an introduction to the thermodynamics of small quantum systems. It is illustrated how the laws of thermodynamics emerge from quantum theory and how open quantum systems can be modeled by Markovian master equations. Quantum systems that are designed to perform a certain task, such as cooling or generating entanglement are considered. Finally, the effect of fluctuations on the thermodynamic description is discussed.

2604.13178 2026-06-10 astro-ph.GA

4MOST ChANGES: Catalog of high-redshift quasar candidates (4.5 < $z$ < 7) selected with SED fitting

4MOST变化:高红移类星体候选者目录(4.5 < z < 7)通过光谱能量分布拟合选择

T. Mkrtchyan, C. Mazzucchelli, R. J. Assef, M. J. Temple, A. Rojas-Lilayú, F. E. Bauer, V. Toptun, J. A. Acevedo Barroso, S. Belladitta, E. P. Farina, L. N. Martínez-Ramírez, G. Papini, S. Satheesh-Sheeba, D. Stern, A. Upadhyayula

AI总结 本文利用多波段光度学和光谱能量分布拟合,在南半球创建了高红移类星体候选者目录,旨在通过4MOST进行光谱验证。

Comments 12 pages, 11 figures, 4 tables, accepted for publication in Astronomy & Astrophysics (A&A)

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Journal ref
A&A 710, A170 (2026)
AI中文摘要

高红移类星体(z > 4.5)的识别对于研究早期宇宙、超大质量黑洞生长和宇宙再电离至关重要。大多数已知的高红移类星体位于北半球,南半球仍有待探索。作为4米多目标光谱望远镜(4MOST)和智利AGN/星系额外银河系调查(ChANGES)S1604调查的一部分,我们旨在利用多波段光度学和光谱能量分布(SED)拟合,创建南半球的高红移类星体候选者目录,以进行4MOST光谱验证。我们通过结合DELVE DR2和DECaLS DR10的光学数据、VHS DR5与VIKING的近红外数据、AllWISE的中红外数据以及Gaia DR3的光学天体测量数据,构建了多波段光度学目录。经过形态和颜色筛选后,我们使用类星体和棕矮星模板进行SED拟合。统计输出,包括χ²、BIC和F检验,用于排名和选择候选者。我们的最终目录包含4.5 < z < 7的6104个高红移类星体候选者,其中在7个或更多光度学波段检测到的候选者满足我们的SED基于选择标准(BIC > 0和F检验 > 10)。使用NTT/EFOSC2和Palomar/NGPS的光谱验证确认了6个观测候选者中有3个高红移类星体(z > 5)。

英文摘要

The identification of high-redshift quasars ($z > 4.5$) is critical for studying the early Universe, supermassive black hole growth, and cosmic reionization. Most known high-redshift quasars are located in the northern hemisphere, leaving the southern sky largely unexplored. As part of the 4-meter Multi-Object Spectroscopic Telescope (4MOST) and Chilean AGN/Galaxy Extragalactic Survey (ChANGES) S1604 survey, we aim to create a large catalog of high-redshift quasar candidates in the southern hemisphere using multiwavelength photometry and Spectral Energy Distribution (SED) fitting, with the goal of spectroscopic follow-up with 4MOST. We construct a multi-band photometric catalog by combining optical data from DELVE DR2 and DECaLS DR10, near-infrared data from VHS DR5 with an additional field of VIKING, mid-infrared data from AllWISE, and optical astrometry from Gaia DR3. After applying morphological and color-based cuts, we perform SED fitting using quasar and brown dwarf templates. Statistical outputs, including $χ^2$, BIC, and F-test are used to rank and select candidates. Our final catalog contains 6104 high-redshift quasar candidates within $4.5 < z < 7$, with detections in 7 or more photometric bands satisfying our SED-based selection criteria (BIC > 0 and F-test > 10). Spectroscopic validation using NTT/EFOSC2 and Palomar/NGPS confirmed 3 high-redshift quasars at $z > 5$ out of 6 observed candidates.

2604.13159 2026-06-10 astro-ph.GA astro-ph.CO

Resolving circumgalactic gas flows around a z$\approx$3.6 quasar using MUSE and ALMA

利用MUSE和ALMA解析z≈3.6类星体周围星系际气体流动

M. Galbiati, A. Pensabene, S. Cantalupo, A. Travascio, G. Pezzulli, R. Decarli, R. Dutta, S. Muzahid, J. Schaye, T. Lazeyras, N. Ledos, G. Quadri, W. Wang

AI总结 研究通过MUSE和ALMA观测分析z≈3.6类星体周围气体动力学,揭示星系际介质的不对称结构及恒星形成区的高密度环境。

Comments Submitted to A&A. 14 pages, 5 figures, 2 appendices

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Journal ref
A&A 710, A117 (2026)
AI中文摘要

星系的形成和演化由与周围大尺度结构的气体交换调控。然而,关于调控气体在星系内外循环的复杂过程仍知之甚少。本文通过高分辨率MUSE观测非共振HeII发射线与ALMA CO(4-3)线测量的准宿主红移,研究了距离类星体约1kpc范围内的冷却电离气体动力学。MUSE观测揭示了复杂的团块结构及延伸约100kpc的弥散发射,相对于类星体系统红移蓝移约0-800km/s,表明星系际介质高度不对称。HeII/Lyα线比值分析及沿类星体视线的低柱密度HI吸收体的存在表明MQN04处于高度电离介质中。气体动力学显示,除最中心区域外,不同示踪剂的径向速度位移一致,表明辐射转移效应较弱。基于其形态和动力学,结论认为扩展的HeII发射可能源于合并驱动的潮汐剥离或受类星体辐射照射的气体流入。在共动兆秒差距尺度上,发现一个大质量密度(δ≈41)的恒星形成星系团,位于距离类星体红移Δv_QSO≤1000km/s范围内。MQN04因此是该时期发现的最过密环境之一。

英文摘要

The formation and evolution of galaxies is regulated by the exchange of gas with the surrounding large-scale structures on circum- and intergalactic scales. Yet, little is known about the complex processes shaping the cycle of baryons in and out of galaxies. In this work, we present a multiline study of the gas surrounding a $z\approx3.66$ quasar known to host one of the brightest Ly$α$ nebulae at high redshift, MUSE Quasar Nebula 04 (MQN04). By combining a high-resolution MUSE detection of non-resonant HeII emission with a precise measurement of the redshift of the quasar host via the ALMA CO(4-3) line, we study the kinematics of the cool ionized gas down to $\approx1\rm\,kpc$ from the quasar. The MUSE observations reveal complex clumpy structures as well as diffuse emission extended over $\approx100\,{\rm kpc}$ and blueshifted by $\approx 0-800\,{\rm km\,s^{-1}}$ relative to the quasar systemic redshift, suggesting that the circumgalactic medium is highly asymmetric. The analysis of the HeII/Ly$α$ line ratio, and the presence of a low-column density ($\approx10^{14.6}~\rm cm^{-2}$) HI absorber along the quasar sightline suggests that MQN04 resides in a highly ionized medium. This is also supported by the gas kinematics, which, except in the most central region, shows consistent velocity shifts across the different tracers, indicative of relatively weak radiative transfer effects. Based on its morphology and kinematics, we conclude that the extended HeII emission may arise from merger-driven tidal stripping or inflows of gas illuminated by the quasar radiation. On comoving megaparsec scales, we discover a large concentration ($δ\approx41$) of star-forming galaxies lying within $|Δv_{\rm QSO}| \leq1000\rm\,km\,s^{-1}$ from the quasar. MQN04 is therefore one of the most overdense environments discovered at this epoch.

2604.12836 2026-06-10 astro-ph.SR

A view of the evolution of a CME and the associated wave-trains at high spatial and temporal resolution

日冕日冕喷流及其相关波浪群的演化观点:高空间和时间分辨率

G. Russano, Y. De Leo, F. Frassati, G. Jerse, V. Andretta, H. Cremades, M. Temmer, S. Mancuso, L. Abbo, A. Burtovoi, F. Landini, M. Pancrazzi, M. Romoli, C. Sasso, R. Susino, M. Uslenghi

AI总结 本文利用高分辨率观测揭示日冕喷流的精细结构和内部等离子体运动,通过波浪前缘的快速传播特性探讨日冕波生成和能量传输机制。

详情
Journal ref
A&A 710, A181 (2026)
AI中文摘要

本文利用高分辨率观测揭示日冕喷流的精细结构和内部等离子体运动,通过波浪前缘的快速传播特性探讨日冕波生成和能量传输机制。

英文摘要

Context. Studying the kinematic and dynamic evolution of fast eruptive events from the middle to high solar corona is a primary objective of the Metis coronagraph on Solar Orbiter. During perihelion, Metis acquires visible light images at a 20s cadence, reaching a spatial resolution of around 2000 km at 0.28 au. This enables capturing coronal mass ejections (CMEs) and transient structures with unprecedented spatial and temporal resolution. Aims. On October 8-9, 2022, an extensive CME was observed by Metis at 0.3 au (resolution: 4.4 $10^{3}$ km/pixel). We aim to exploit this high resolution to resolve multiple substructures within the CME front, revealing plasma elements with distinct trajectories and speeds to provide a detailed kinematic characterization of the eruption. Methods. A normalization-based running difference algorithm was applied to enhance the complex morphology. Height-time diagrams were used to estimate propagation speeds and frequency variations. A 3D flux rope reconstruction, combined with multi-spacecraft coronagraphs and disk imagers, enabled tracking the CME from its initiation in the lower corona to approximately 5 solar radii. Joint observations with Solar Orbiter EUI-FSI provided insights into the eruption's onset, while Metis captured its development into the middle corona. Results. Metis observations resolve the CME's fine structure and internal plasma motions. The detection of circular, fast-propagating wavefronts (500 km/s, 3 minute period) at the western flank suggests wave excitation and magnetic reconfiguration processes. Multiple interpretations are proposed for these coronal wave trains, including quasi periodic propagating fast modes, offering new insights into wave generation and energy transport in the solar corona.

2604.12109 2026-06-10 astro-ph.GA

Identifying Changing-Look AGN Transitions in Light Curve Data with the Zwicky Transient Facility

利用Zwicky瞬态设施数据识别变化型活动星系核的转变

Margaret E. Verrico, K. Decker French, Vivienne F. Baldassare, Colin J. Burke, Laura Duffy, Nicholas Earl, Megan Harrison, Jason T. Hinkle, Alexander Messick, Samaresh Mondal, Yashasvi Moon, Margaret Shepherd, Zachary Stone

AI总结 本文提出基于光度学指标识别变化型活动星系核转变的方法,通过分析g波段亮度和g-r色度变化,发现该方法在ZTF六年内能识别9.6%的CL-AGN宿主,同时估计了假阳性率和不同 Seyfert 类型的 flare 率。

Comments 25 pages, 11 figures, to be re-submitted to ApJ after a positive referee report. Comments welcome!

详情
AI中文摘要

Changing-Look AGN (CL-AGN) 是在塞弗特型之间转换的活动星系核,挑战了活动星系核统一模型。大多数CL-AGN通过重复光谱学识别,难以确定转换的持续时间和幅度。因此,这种转换背后的物理机制仍未知。我们利用合成光度学与ZTF光变曲线数据,开发了一种新的标准来基于g波段亮度和g-r色度的变化识别光度学CL-AGN转变。我们发现,CL-AGN标准为|Δg|>0.4 mag和|Δ(g-r)|>0.2 mag,在六年的ZTF调查中恢复了9.6±4.9−3.4%的CL-AGN宿主,包括SDSS J084957.78+274728.9的候选重复变化-look事件。通过模拟AGN光变曲线,我们估计在模拟的塞弗特中假阳性率为1.6±0.19−0.17%。我们发现,在六年内,I型塞弗特的类似爆发率为1.2±0.87−0.50%,II型塞弗特的爆发率≤0.39%。光度学CL-AGN转变持续时间在21至560天之间,中位数持续时间为360天,与AGN盘的热或轨道时间尺度一致。我们未检测到黑洞质量与转换持续时间之间的相关性,这可能是由于检测到的光度学转换样本较小。此方法可应用于即将到来的遗产调查空间时间项目,以识别CL-AGN候选者并测试其起源理论。

英文摘要

Changing-Look AGN (CL-AGN) are AGN which transition between Seyfert types, challenging AGN unification models. Most CL-AGN have been identified via repeat spectroscopy, making it difficult to determine the duration and magnitude of the CL-AGN transition. As such, the physical mechanisms behind this transition are still unknown. We use synthetic photometry in combination with ZTF light curve data to develop a new criterion to identify photometric CL-AGN transitions based on changes in g-band magnitude and g-r color. We find that a CL-AGN criterion of $| Δg| > 0.4$ mag and $| Δ(g-r)| > 0.2$ mag recovers a photometric transition in $9.6^{+4.9}_{-3.4}\%$ of CL-AGN hosts over the six-year ZTF survey, including a candidate repeating changing-look event in SDSS J084957.78+274728.9. Using simulated AGN light curves, we estimate the false positive rate among the simulated Seyferts to be $1.6^{+0.19}_{-0.17}\%$. We find that the rate of similar flares among Type 1 Seyferts is $1.2^{+0.87}_{-0.50}\%$ , and among Type 2 Seyferts is $\leq 0.39\%$ over six years. Photometric CL-AGN transitions last between 21 and 560 days, with a median duration of 360 days, consistent with the thermal or orbital timescales for AGN disks. We do not detect a correlation between black hole mass and transition duration, likely due to the small sample of detected photometric transitions. This method can be applied to the upcoming Legacy Survey of Space and Time to identify CL-AGN candidates and test theories of their origins

2604.11765 2026-06-10 astro-ph.SR astro-ph.GA

NGC 1647: A young open cluster with a broad main sequence observed with LAMOST

NGC 1647:一个年轻开放星团的广谱主序星观测结果

A. Frasca, M. Qin, J. ALonso-Santiago, G. Catanzaro, J. N. Fu, J. Y. Zhang, A. Bragaglia

AI总结 利用LAMOST数据研究NGC 1647星团成员的恒星参数、活动水平和锂丰度,揭示星团中存在差异性红化现象,确定其年龄为203±27 Myr。

Comments 17 pages, 20 figures, accepted by Astronomy & Astrophysics for publication

详情
Journal ref
A&A 710, A164 (2026)
AI中文摘要

本文通过分析NGC 1647星团候选成员的中分辨率LAMOST光谱,确定恒星参数、活动水平、锂丰度及星团特性。使用ROTFIT代码分析158个成员的大气参数(Teff、log g、[Fe/H])、径向速度(Vr)和投影旋转速度(vsini)。对太阳型和较冷恒星计算H-α和LiI-6708净等效宽度。通过TESS光度数据确定160颗恒星的自转周期。发现四个双星系统并给出两星径向速度。星团成员的Vr分布峰值为-5.3 km/s,标准差为1.6 km/s,平均金属度为[Fe/H]=-0.08±0.08 dex。通过160个可能成员的光谱能量分布推断出星团场中存在差异性红化,平均值为A_V=1.1 mag。A_V值与主序下边界色偏有显著相关性,但与vsini无关。这两个发现证实差异性红化是导致该星团观测到的扩展主序转折点(eMSTO)的主要驱动因素。通过锂丰度确定NGC 1647的年龄为203±27 Myr,与通过自转chronological方法和等时线拟合推断的值一致。

英文摘要

In this work we present the results of our analysis of medium-resolution LAMOST spectra of candidate members of the cluster NGC 1647 with the aim of determining the stellar parameters, activity level, lithium abundance, and to study the cluster properties. We used the code ROTFIT to determine the atmospheric parameters (Teff, logg, and [Fe/H]), radial velocity (Vr), and projected rotation velocity (vsini) for 158 cluster members. Moreover, for solar-type and cooler stars (Teff< 6500 K), we calculated the H-alpha and LiI-6708 net equivalent width by means of the subtraction of inactive photospheric templates. We determined the rotation periods for 160 stars by analyzing the available TESS photometry. We found four double-lined spectroscopic systems for which we provide the radial velocities of the two components. The Vr distribution of the cluster members peaks at -5.3 km/s with a dispersion of 1.6 km/s, while the average metallicity is [Fe/H]=-0.08$\pm$0.08 dex, in line with previous determinations. From the fitting of the spectral energy distribution of 160 likely members we infer the existence of a differential reddening across the cluster field with an average value of $A_V$=1.1 mag. The $A_V$ values show a distinct correlation with the color offset from the lower boundary of the main sequence; conversely, this offset appears to be uncorrelated with vsini. These two findings confirm that differential reddening is the primary driver behind the observed extended Main-Sequence Turn-Off (eMSTO) in this cluster. The age of NGC 1647, obtained from the lithium abundance, is 203$\pm$27 Myr, which is compatible with the values inferred from a gyrochronological approach and the isochrone fitting.

2604.11310 2026-06-10 astro-ph.HE

A Ring of Fire Orphan γ-Ray Flare in the Neutrino Candidate 3C 120

环火孤立γ射线暴在中微子候选体3C 120中

E. Traianou, G. Bruni, J. Rodi, G. F. Paraschos, S. G. Jorstad, A. P. Marscher, A. Lähteenmäki, M. Tornikoski, J. Tammi, I. Agudo

AI总结 研究通过VLBI观测揭示3C 120在2018年最亮γ射线暴期间的孤立暴发,发现喷流扰动与同步辐射光子逆康普顿散射的关系,提出环火机制解释γ射线亮度。

Comments 10 pages, 2 figures

详情
Journal ref
A&A 710, A123 (2026)
AI中文摘要

我们呈现了3C~120在2018年3月最亮γ射线暴期间的43GHzVLBI观测。尽管γ射线功率达到3.7×10^44 erg/s,但同时进行的X射线监测未发现0.3-200keV范围内的变化,也未在B、V、R和I波段光学观测或37和235GHz观测中发现变化,证实了孤立暴发。高时间分辨率的VLBI成像识别出一个新的喷流扰动(N),以β_app = (2.8 ± 1.3)的速度通过准静态特征C1-C3。γ射线峰值与N穿过C3(r ~ 0.38 mas)的时间和空间位置一致,我们测得极化率增加5倍(m = 16%)和Δχ ~ 24° EVPA旋转,表明局部磁场压缩。极端的康普顿主导(L_γ/L_syn,blob ≈ 160)自然由环火情景解释,其中N(Γ_blob = 6,B_blob = 0.023 G)逆康普顿散射来自C3的同步辐射光子,重现了观测到的γ射线亮度。与2014-2015年归因于BLR附近快速脊柱重定向的孤立暴发不同,2018年的事件代表了不同的物理机制,即传播扰动与静态喷流结构在约10倍BLR半径处的相互作用。这项工作为射电星系中VLBI解析喷流动态与孤立γ射线发射之间的首次直接观测联系提供了依据。

英文摘要

We present 43\,GHz VLBI observations of the radio galaxy 3C~120 during its brightest $γ$-ray outburst (March 2018), recently associated with the IceCube neutrino alert IC-180213A. Despite reaching $L_γ= 3.7 \times 10^{44}$\,erg\,s$^{-1}$, contemporaneous X-ray monitoring from INTEGRAL/ISGRI, MAXI/GSC, and \textit{Swift}/XRT revealed no variability across 0.3-200\,keV, nor in B, V, R, and I band optical observations or 37 \& 235\,GHz observations, establishing an orphan flare. High-cadence VLBI imaging identified a new jet disturbance (N) propagating at $β_{\rm app} = (2.8 \pm 1.3)$ through quasi-stationary features C1-C3. The $γ$-ray peak coincided spatially and temporally with N crossing C3 ($r \sim 0.38$\,mas), where we measured a factor-of-5 increase in fractional polarization ($m = 16\%$) and $Δχ\sim 24^\circ$ EVPA rotation, indicating localized magnetic field compression. The extreme Compton dominance ($L_γ/ L_{\rm syn,blob} \approx 160$) is naturally explained by the Ring of Fire scenario, in which N ($Γ_{\rm blob} = 6$, $B_{\rm blob} = 0.023$\,G) inverse-Compton scatters synchrotron photons from C3, reproducing the observed $γ$-ray luminosity for physically reasonable parameters. Unlike the 2014-2015 orphan flares attributed to rapid spine reorientation near the BLR, the 2018 event represents a distinct physical mechanism, a propagating disturbance interacting with stationary jet structure at $\sim10\times$ the BLR radius.This work provides the first direct observational link between VLBI-resolved jet dynamics and orphan $γ$-ray emission in a radio galaxy.

2604.11292 2026-06-10 astro-ph.EP astro-ph.SR

Compact CO emission and no evidence of radial drift. ALMA observations of the faintest planet-forming disks in Lupus

紧凑的CO发射和没有径向漂移的证据。ALMA对猎户座中最暗弱的行星形成盘的观测

Giulia Ricciardi, Francesco Zagaria, Anna Miotello, Carlo F. Manara, Giovanni Rosotti, Luigi Zallio, Sean Andrews, Richard Booth, John Carpenter, Ilse Cleeves, Stefano Facchini, Viviana V. Guzmán, Claudia Toci, Miguel Vioque, David Wilner, Jonathan P. Williams

AI总结 通过ALMA观测猎户座最暗弱的行星形成盘,研究紧凑盘结构是否能解释弱CO发射,发现部分盘可能原本紧凑,无尘埃漂移证据。

详情
Journal ref
A&A 710, A112 (2026)
AI中文摘要

大量观测到的行星形成盘显示弱CO发射,常解释为强CO耗尽。但弱发射也可能源于未解析的盘,其大小被高估,使它们看起来暗淡。先前观测灵敏度有限,阻碍了这一场景的检验,影响了盘演化和行星形成理解。本文通过ALMA Band 7观测12CO (J=3-2)和13CO (J=3-2)的17个最暗弱盘,评估紧凑盘结构是否能解释其弱CO发射。数据达到0.25角秒的角分辨率(约20 au在160 pc处)且比存档观测深一个数量级。应用线堆叠增强灵敏度,并将推导的CO光度与紧凑和扩展盘的物理化学模型比较,估算气体和尘埃尺寸。10个盘检测到两种同位素,4个仅检测到12CO,3个未检测到。几个盘与紧凑且光学厚一致,提供CO耗尽场景的替代解释。推导的气体半径(Rco小于40 au)支持此解释,表明盘可能原本紧凑,符合最近的Class 0/I结果。气体-尘埃尺寸比无明显尘埃演化证据,表明这些盘不是漂移主导。

英文摘要

A large fraction of planet-forming disks observed with ALMA show faint CO emission, often interpreted as strong CO depletion. However, faint emission may also arise from spatially unresolved disks, whose sizes are overestimated, making them appear intrinsically faint. The limited sensitivity of previous observations has prevented testing this scenario, hindering our understanding of disk evolution and planet formation. We present new ALMA Band 7 observations of 12CO (J=3-2) and 13CO (J=3-2) in 17 of the faintest disks in Lupus, aiming to assess whether compact disk structure can explain their weak CO emission. The data reach an angular resolution of 0.25arcsec (about 20 au at 160 pc) and are an order of magnitude deeper than archival observations. We apply line stacking to enhance sensitivity and compare the derived CO luminosities with physical-chemical models of compact and extended disks, also estimating gas and dust sizes. We detect both isotopologues in 10 disks, only 12CO in 4, and neither in 3. Several disks are consistent with being intrinsically compact and optically thick in both lines, providing an alternative to the CO depletion scenario. The inferred gas radii (Rco less than 40 au) support this interpretation and suggest that a significant fraction of disks may be born compact, in line with recent Class 0/I results. Gas-to-dust size ratios show no clear evidence for dust evolution, indicating these disks are not drift-dominated.

2604.11247 2026-06-10 astro-ph.SR astro-ph.EP astro-ph.GA

Observations of highly inclined disks with ALMA. Results from 12CO gas and continuum observations

用ALMA观测高倾角盘. 12CO气体和连续观测的结果

Laurine Martinien, Gaspard Duchêne, Álvaro Ribas, Marion Villenave, François Ménard, Karl R. Stapelfeldt, Christophe Pinte

AI总结 研究高倾角原行星盘中12CO气体、毫米尘埃热发射和光学/近红外散射光的径向和垂直范围,通过14个样本发现气体和尘埃的延伸关系及垂直结构,首次估算动力学质量并发现质量与倾角的反相关性。

Comments Accepted for publication in A&A. 16 pages,10 figures

详情
Journal ref
A&A 710, A140 (2026)
AI中文摘要

我们旨在研究高倾角原行星盘中12CO气体、毫米尘埃热发射和光学/近红外散射光的径向和垂直范围。我们分析了14个高倾角原行星盘的样本。我们提供了ALMA高角分辨率带7(0.9毫米)连续图像和12CO(3-2)气体矩形图以及HST和VLT/SPHERE散射光图像。我们样本中的大多数盘(14个中的11个)遵循Rgas > Rdust,micron > Rdust,mm。其他3个盘在毫米连续波段比在散射光中更延伸。高倾角盘在CO气体线发射中比在毫米尘埃连续波段更不延伸,这与低倾角盘相比。这源于光学深度效应和/或径向漂移。已知的盘大小与毫米连续和线发射量的相关性在我们的样本中得到确认,高倾角盘比低倾角盘在相同盘半径下更暗。我们发现,一旦将发射量校正为盘倾角,这一相关性显著加强,与毫米波长下盘高度光学厚一致。关于垂直范围定义为发射高度的 apparent 发射高度,我们样本中的大多数盘遵循Hgas > Hdust,mm。这加强了我们之前的发现,即毫米尘埃高度脱耦于气体,并由于垂直沉降形成盘中平面层。大多数盘在气体中比在散射光中更垂直延伸,表明微米级尘埃并未完全耦合到气体中。我们还首次使用PV图对样本中的大多数对象估计了动力学质量。我们发现动力学质量与aspect ratio之间存在反相关性,强调了重力在设定盘垂直范围中的主导作用,但没有与盘半径相关联。

英文摘要

[Abridged] We aim to study the radial and vertical extents of 12CO gas, millimeter dust thermal emission and optical/NIR scattered light by dust in disks. We analyze a sample of 14 highly inclined protoplanetary disks. We present ALMA high angular resolution band 7 (0.9 mm) continuum images and 12CO (3-2) gas moment maps as well as HST and VLT/SPHERE scattered light images. The majority of disks in our sample (11 out of 14) follow Rgas > Rdust,micron > Rdust,mm. The other 3 disks appear more extended in millimeter continuum than in scattered light. Highly inclined disks tend to appear less radially extended in CO gas line emission than in millimeter dust continuum compared to less inclined disks. This results from optical depth effects and/or radial drift. The known correlation between disk size and millimeter continuum and line fluxes are confirmed in our sample with highly inclined disks significantly fainter than disks seen at lower inclination for a given disk radius. We found that this correlation is significantly tightened once fluxes are corrected for the disk inclination, consistent with the disks being optically thick at millimeter wavelengths. Regarding the vertical extent defined as the apparent emitting height, most disks in our sample follow Hgas > Hdust, mm. This strengthens our previous findings that the millimeter dust is highly decoupled from the gas and forms a layer in the disk midplane due to vertical settling. Most disks appear more vertically extended in gas than in scattered light, suggesting that the micron-sized dust is not fully coupled to the gas. We also estimated dynamical masses using PV diagrams for the first time for most of the objects in our sample. We found an anti-correlation between the dynamical mass and the aspect ratio, emphasizing the dominant role of gravity in setting the disk vertical extent, but no correlation with the disk radius.

2604.08934 2026-06-10 cond-mat.str-el

Evolution of crystal field and intraionic interactions in the ilmenite $A$IrO$_3$ ($A$ = Mg, Zn, Cd) and hyperhoneycomb $β$-ZnIrO$_3$

ilmenite $A$IrO$_3$ ($A$ = Mg, Zn, Cd) 和 hyperhoneycomb $β$-ZnIrO$_3$ 中的晶场和离子间相互作用的演变

Yuya Haraguchi, Hiroko Aruga Katori, Kenji Ishii, Hakuto Suzuki

AI总结 通过Ir L3边共振非弹性x射线散射研究ilmenite iridates和hyperhoneycomb结构的局部电子结构,揭示了化学取代对晶场和离子间相互作用参数的影响,为理解Kitaev候选材料中的磁学行为提供了基础。

详情
Journal ref
Physical Review B 113, 235114 (2026)
AI中文摘要

具有$t_{2g}^5$电子配置的自旋轨道Mott绝缘体是Kitaev反铁磁液体的有希望平台,但需要精细调节其晶体结构以抑制非Kitaev相互作用。本文通过Ir L3边共振非弹性x射线散射研究了ilmenite iridates $A$IrO$_3$ ($A$ = Mg, Zn, Cd) 和 hyperhoneycomb $β$-ZnIrO$_3$ 的局部电子结构。多重分析显示,随着A位离子半径的增加,三重畸变增强,这为偏离理想J=1/2态和在CdIrO$_3$中观察到的反铁磁相互作用提供了微观解释。此外,ilmenite ZnIrO$_3$和hyperhoneycomb $β$-ZnIrO$_3$的局部多重参数几乎相同,表明其不同的磁基态主要由不同的晶格结构而非单离子性质决定。这些发现为理解局部晶场畸变如何控制Kitaev候选材料中的磁学哈密顿量奠定了基础。

英文摘要

Spin-orbit Mott insulators with the $t_{2g}^5$ electron configuration are promising platforms for the Kitaev spin liquid, yet fine-tuning of their crystal structures is essential to suppress non-Kitaev interactions. Here, we investigate the local electronic structures of the ilmenite iridates $A\mathrm{IrO}_3$ ($A = \mathrm{Mg}, \mathrm{Zn}, \mathrm{Cd}$) and the hyperhoneycomb $β\text{-}\mathrm{ZnIrO}_3$ using Ir $L_3$-edge resonant inelastic x-ray scattering (RIXS). Multiplet analysis of the RIXS spectra reveals a systematic evolution of the crystal field and intraionic interaction parameters upon chemical substitution at the $A$-site. We observe an enhancement of the trigonal distortion with increasing $A$-site ionic radius. This provides a microscopic explanation for the deviation from the ideal $J=1/2$ state and the antiferromagnetic interactions identified in $\mathrm{CdIrO}_3$. Furthermore, the local multiplet parameters of ilmenite $\mathrm{ZnIrO}_3$ and hyperhoneycomb $β\text{-}\mathrm{ZnIrO}_3$ are found to be nearly identical, demonstrating that their different magnetic ground states are primarily governed by their distinct lattice structures rather than the single-ion properties. These findings establish a solid foundation for understanding how local crystal-field distortions control the magnetic Hamiltonian in Kitaev candidate materials.

2603.07340 2026-06-10 cond-mat.str-el cond-mat.mtrl-sci

Controlling Projection-Space Artifacts in DFT+U via Projection-Consistent U_{eff}

通过投影一致的U_eff控制DFT+U中的投影空间伪影

Manjula Raman, Kenneth Park

AI总结 本文研究了DFT+U中有效U_eff对局部投影空间大小的依赖性,通过一致确定U_eff消除投影伪影,提升计算可靠性。

详情
Journal ref
APL Computational Physics 2, 026110 (2026)
AI中文摘要

密度泛函理论结合Hubbard修正(DFT+U)广泛用于处理局域电子态,但其预测常受局部投影空间定义相关联的关联子空间的选择影响。这种敏感性对计算可重复性构成实际挑战,尤其当投影参数在不同代码、基组或材料间变化时。本文系统研究了在全电子APW+lo计算中,通过受限密度泛函理论确定的U_eff如何依赖于局部投影空间的大小。使用金红石和钛酸盐TiO₂和β-MnO₂作为代表性测试案例,表明在不同投影选择中应用单一固定U_eff会引入人工投影驱动的总能量误差,包括虚假的磁序转变和不合理的相稳定性敏感性。当U_eff在内部一致地为每个投影空间确定时,可以消除这些伪影,从而获得投影一致的DFT+U预测,包括晶格参数、相能学和磁基态。通过分析总能量趋势以及局部d轨道的空间特性,证明随着投影空间增大,U_eff系统性减少源于轨道弛豫和增强的电子屏蔽,与轨道空间扩展有关。这些结果提供了一个物理驱动的框架,用于控制DFT+U计算中的投影空间伪影,并在不同相关材料和计算设置中获得能量稳健的预测。

英文摘要

Density functional theory augmented with a Hubbard correction (DFT+U) is widely used to treat localized electronic states, but its predictions are often sensitive to the choice of the local projection space defining the correlated subspace. This sensitivity poses a practical challenge for computational reproducibility, particularly when projection parameters vary across codes, basis sets, or materials. In this work, we systematically investigate how the effective on-site Coulomb interaction $U_{\mathrm{eff}}$, determined \textit{ab initio} using constrained density functional theory, depends on the size of the local projection space in all-electron APW+lo calculations. Using rutile and anatase TiO$_2$ and $β$-MnO$_2$ as representative test cases, we show that applying a single fixed $U_{\mathrm{eff}}$ across different projection choices introduces artificial projection-driven errors in total energies, including spurious magnetic ordering transitions and unphysical sensitivity of phase stability. These artifacts are eliminated when $U_{\mathrm{eff}}$ is determined in an internally consistent manner for each projection space, yielding projection-consistent DFT+U predictions for lattice parameters, phase energetics, and magnetic ground states. By analyzing total-energy trends alongside the spatial characteristics of the localized $d$ orbitals, we demonstrate that the systematic reduction of $U_{\mathrm{eff}}$ with increasing projection size originates from orbital relaxation and enhanced electronic screening associated with orbital spatial extension. These results provide a physically motivated framework for controlling projection-space artifacts in DFT+U calculations and for obtaining energetically robust predictions across diverse correlated materials and computational setups.

2507.20488 2026-06-10 math.AP math-ph math.MP math.OC

Linear toroidal-inertial waves on a differentially rotating sphere with application to helioseismology: Modeling, forward and inverse problems

线性双极-惯性波在差分旋转球体上的建模及其在日震学中的应用:建模、正反问题

Tram Thi Ngoc Nguyen, Damien Fournier, Laurent Gizon, Thorsten Hohage

AI总结 本文发展了解释太阳惯性波观测的数学框架,通过差分旋转球体上的纯双极线性波假设,推导出流函数的四阶标量方程,并证明了在显式条件下的波解well-posedness,研究了从完整或部分表面数据同时重建粘性和差分旋转参数的反问题,证明了迭代正则化方法的收敛性及参数的局部唯一可识别性。

详情
Journal ref
Mathematical Methods in the Applied Sciences (2026): 1-27
AI中文摘要

本文发展了解释太阳惯性波观测的数学框架,假设在理想化设定下纯双极线性波,流函数满足四阶标量方程。在显式差分旋转条件下证明波解的well-posedness。研究了从完整或部分表面数据同时重建粘性和差分旋转参数的反问题,通过验证切向锥条件证明迭代正则化方法的收敛性,并证明未知参数的局部唯一可识别性。数值实验表明Nesterov-Landweber迭代在不同观测策略和噪声水平下具有稳健的重建能力。

英文摘要

This paper develops a mathematical framework for interpreting observations of solar inertial waves in an idealized setting. Under the assumption of purely toroidal linear waves on the sphere, the stream function of the flow satisfies a fourth-order scalar equation. We prove well-posedness of wave solutions under explicit conditions on differential rotation. Moreover, we study the inverse problem of simultaneously reconstructing viscosity and differential rotation parameters from either complete or partial surface data. We establish convergence guarantee of iterative regularization methods by verifying the tangential cone condition, and prove local unique identifiability of the unknown parameters. Numerical experiments with Nesterov-Landweber iteration confirm reconstruction robustness across different observation strategies and noise levels.

2601.05916 2026-06-10 astro-ph.GA

Evaluating star formation rates at z = 5

在z=5时评估恒星形成率

D. Ismail, K. Kraljic, M. Béthermin, A. U. Kapoor, F. Renaud, C. Accard, J. Freundlich, Y. Dubois, S. Han, J. K. Jang, S. Jeon, T. Kimm, J. Rhee, S. Yi

AI总结 研究通过模拟探讨z=5时期恒星形成率的系统误差和偏差,发现基于Hα、红外和混合数据的SFR方法各有优劣,其中混合方法在减少散射方面更有效。

Comments Accepted for publishing in A&A (aa58893-26), 16 pages, 16 figures

详情
Journal ref
A&A 710, A102 (2026)
AI中文摘要

推断高红移星系的恒星形成率(SFR)仍然具有挑战性,由于观测限制或校准方法的不确定性。我们利用NewHorizon和NewCluster两个最先进的流体动力学模拟,结合辐射传输代码Skirt进行后处理,研究z=5星系推断SFR的系统误差和偏差;这是一个星系积累恒星质量的时期。我们为广泛使用的示踪剂创建了合成观测数据:Hα发射线、[CII] 158微米细结构线、总红外(IR)连续体辐射和混合(IR + UV)。发现Hα推断的SFR在10 Myr时间平均下对校准选择敏感,其散射由尘埃消光、视向角和尘埃-金属比驱动。采用更陡的消光曲线可显著减少散射,但无法完全消除系统误差。基于红外连续体的SFR在有良好采样的连续体发射(8至1000微米)时可追踪100 Myr时间平均的内在SFR,但在红外数据有限时则低估。然而,红外SFR显示出显著的散射,主要由于紫外光子泄漏和星形成历史的强烈变化。当紫外数据可用时,混合(IR + UV)SFR提供更稳健的估计,比基于红外的SFR减少散射,同时避免了显式消光修正。最后,我们推导出[CII]-SFR关系,发现其比以前的研究更陡,但散射与气体密度和金属性有关。总体而言,基于红外、混合和[CII]的示踪剂比Hα更稳健,对光学深度的变化更鲁棒。

英文摘要

Inferring the star formation rates (SFR) in high redshift galaxies remains challenging, owing to observational limitations or uncertainties in calibration methods that link luminosities to SFRs. We utilize two state-of-the-art hydrodynamical simulations NewHorizon and NewCluster, post-processed with the radiative transfer code Skirt, to investigate the systematic uncertainties and biases in the inferred SFRs for z=5 galaxies; an epoch where galaxies build-up their stellar mass. We create synthetic observables for widely-used tracers: Halpha nebular line, [CII] 158 micron fine-structure line, total infrared (IR) continuum luminosity, and hybrid (IR + UV). We find that Halpha-inferred SFRs, time-averaged over 10 Myr, are sensitive to the choice of calibration and exhibit substantial scatter driven by dust attenuation, viewing angle, and dust-to-metal ratio. Adopting a steeper attenuation curve reduces this scatter significantly but does not fully eliminate systematic uncertainties. IR continuum-based SFRs trace intrinsic SFRs time-averaged over 100 Myr timescales when a well-sampled continuum emission between restframe 8 and 1000 micron is available and underestimate them with typical approaches when IR data are limited. Nevertheless, IR SFRs display a considerable scatter, largely due to UV photon leakage and strong variations in the star formation history. When UV data are available, hybrid (IR + UV) SFRs provide a more robust estimate, reducing scatter compared to IR-based SFRs while avoiding explicit attenuation corrections. Finally, we derive a [CII]-SFR relation finding a steeper relation than previous studies, however with significant scatter linked to gas density and metallicity. Overall, IR-, hybrid-, and [CII]-based tracers remain more robust than Halpha against variations in optical depth.

2504.11099 2026-06-10 math.CT

Double categories of profunctors

双范畴的联络函子

Yuto Kawase

AI总结 本文通过引入双范畴余极限的概念,严格刻画了富集范畴、函子和联络函子的虚拟双范畴,强调在对象层面的等价性和富集在虚拟双范畴中的统一性。

Comments 82 pages; v4: final journal version. Added comparison with related notions; added Appendix A; refined the proof of the main theorem; and more

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Journal ref
Appl. Categ. Structures 34 (4) (2026), Paper No. 33
AI中文摘要

我们通过引入一个新的双范畴余极限的概念,来刻画虚拟双范畴中的富集范畴、函子和联络函子。我们的刻画是严格的,即在虚拟双范畴之间是等价的,在对象层面则是富集范畴的等价。本文中,我们以增强的虚拟双范畴作为双范畴概念的基本语言,而不是双范畴或单向范畴,以获得更清晰的拼接图示。

英文摘要

We characterize virtual double categories of enriched categories, functors, and profunctors by introducing a new notion of double-categorical colimits. Our characterization is strict in the sense that it is up to equivalence between virtual double categories and, at the level of objects, up to isomorphism of enriched categories. Throughout the paper, we treat enrichment in a unital virtual double category rather than in a bicategory or a monoidal category, and, for consistency and better visualization of pasting diagrams, we adopt augmented virtual double categories as a fundamental language for double-categorical concepts.

2604.03142 2026-06-10 astro-ph.SR astro-ph.GA

Isochrone-cloud fitting and asteroseismology of the Kepler open cluster NGC6866

等时线-云拟合与开普勒开放星团NGC6866的恒星地震学

Haotian Wang, Gang Li, Dario J. Fritzewski, Timothy Van Reeth, Conny Aerts

AI总结 研究不同输入物理和初始条件计算的等时线对开普勒开放星团NGC6866年龄测定的影响,并与来自开普勒光度计的恒星地震学年龄进行比较。利用Gaia DR3数据识别180个星团成员,开发了考虑输入物理中范围参数的等时线-云拟合方法,识别出变星并进行建模。

Comments Accepted for publication on A&A, 29/03/2026. Total 13 pages of main text with 13 figures, 3 pages of appendix with 5 figures

详情
Journal ref
A&A 710, A148 (2026)
AI中文摘要

我们研究了不同输入物理和初始条件计算的等时线对开普勒开放星团NGC6866年龄测定的影响,并与来自开普勒光度计的恒星地震学年龄进行比较。利用Gaia DR3数据,我们通过聚类算法识别了180个星团成员。然后,我们开发了一种等时线-云拟合方法,该方法考虑了输入物理中的范围参数。随后,我们从星团成员中识别出变星。对于19个g模式脉动星,我们使用专门的旋转恒星模型网格进行建模,这些模型受光谱学和光度学参数、渐近重力模式周期间隔以及近核心旋转率的约束。我们考虑了两种情况:对每个脉动星单独建模,以及在假设共同星团年龄的情况下进行建模。PARSEC和MIST等时线分别给出690和467百万年不同的年龄。等时线-云拟合表明初始临界旋转分布峰值为0.6,比来自恒星地震学的推断高约一倍。地震建模显示地震质量和等时线质量之间的一致性,但由于内部混合差异导致的年龄差异显著。当g模式脉动星以共享星团年龄进行建模时,我们得到759百万年,与PARSEC等时线年龄一致。我们得出结论,开放星团的年龄测定对所采用的输入物理和初始条件敏感,突显了需要更精确校准的恒星演化学模型的必要性。

英文摘要

We investigate how isochrones computed with different input physics and initial conditions affect the age dating of the open cluster NGC 6866, and compare the results with asteroseismic ages derived from Kepler photometry. Using Gaia DR3 data, we identified 180 cluster members with a clustering algorithm. We then developed an isochrone-cloud fitting method that accounts for a range of free parameters in the input physics. Variable stars were subsequently identified among the cluster members. For 19 g-mode pulsators, we carried out modelling with a dedicated grid of rotating stellar models, constrained by spectroscopic and photometric parameters, the asymptotic gravity-mode period spacing, and the near-core rotation rate. We considered two cases: modelling each pulsator individually and modelling them under the assumption of a common cluster age. PARSEC and MIST isochrones yield discrepant ages of 690 and 467 Myr, respectively. The isochrone-cloud fit indicates an initial critical rotation distribution peaking at 0.6, about a factor of two higher than inferred from asteroseismology. The seismic modelling shows agreement between seismic and isochronal masses, but substantial differences in the derived ages due to differences in internal mixing. When the g-mode pulsators are modelled with a shared cluster age, we obtain 759 Myr, consistent with the PARSEC isochronal age. We conclude that age dating of open clusters is sensitive to the adopted input physics and initial conditions, highlighting the need for better calibrated stellar evolutionary models.

2506.08993 2026-06-10 hep-ph astro-ph.CO astro-ph.HE

The Highest-Energy Neutrino Event Constrains Dark Matter-Neutrino Interactions

最高能量中微子事件限制了暗物质-中微子相互作用

Toni Bertólez-Martínez, Gonzalo Herrera, Pablo Martínez-Miravé, Jorge Terol Calvo

AI总结 利用KM3NeT观测到的最高能量中微子事件,研究暗物质-中微子相互作用对中微子传播的影响,并推导出相关限制。

Comments v2: Matches published version. Addition of unitarity bounds to cross-sections that alter the conclusions. 16 pages, 4 figures

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Journal ref
Phys. Rev. D 113, 103052 (2026)
AI中文摘要

暗物质-中微子相互作用会影响天体物理中微子的传播,减弱到达地球的中微子通量。利用KM3NeT合作组织检测到的最高能量中微子事件作为例子,假设其来自 extragalactic,推导出在 $E_ν= 220^{+570}_{-110}\, \mathrm{PeV}$ 时的相互作用限制。考虑仅在银河系暗物质晕中的传播,得出暗物质候选者的质量范围内,相互作用截面满足 $σ_{\rm DM-ν}/m_{\rm DM} \lesssim 10^{-22}\, \mathrm{cm}^2\,\mathrm{GeV}^{-1}$。如果瞬时源被确认,高能中微子会穿过源宿主的暗物质晕,导致更严格的限制(例如,假设PKS 0605-085是源,可达到6个数量级)。这些对暗物质-中微子相互作用截面的限制转化为对暗物质候选者质量、介质质量及耦合强度的限制。我们发现,对于这些简化模型,KM3-230213A高能事件的约束在质量超过MeV时几乎被单位性约束排除。因此,此类高能中微子的衰减要求更丰富的暗物质领域以产生有意义的限制。

英文摘要

Dark Matter-neutrino interactions affect the propagation of astrophysical neutrinos, attenuating the flux of neutrinos arriving at Earth. Using the highest-energy neutrino event detected to date by the KM3NeT collaboration as an example, and assuming an extragalactic origin, we derive limits on these interactions at $E_ν= 220^{+570}_{-110}\, \mathrm{PeV}$. Considering only the propagation on the Milky Way Dark Matter halo, we constrain the interaction cross section over the mass of the Dark Matter candidate to be, $σ_{\rm DM-ν}/m_{\rm DM} \lesssim 10^{-22}\, \mathrm{cm}^2\,\mathrm{GeV}^{-1}$. If a transient source was positively identified, the high-energy neutrino would have crossed the dark-matter halo of the source host as well, resulting in more stringent constraints (e.g., up to $ \sim$ 6 orders of magnitude assuming the blazar PKS 0605-085 is the source). These bounds on the Dark Matter-neutrino interaction cross section are translated into limits on the mass of the Dark Matter candidate, the mass of the mediator, and the coupling strength for different simplified models. We find that the constraints from the KM3-230213A high-energy event for these simplified models are almost entirely ruled out for masses above the MeV by unitarity constraints. Therefore, the attenuation of such energetic neutrinos by Dark Matter calls for richer dark sectors in order to produce meaningful constraints.

2603.29151 2026-06-10 hep-th

What U Can Do: New Solutions and New Challenges Beyond Leading Order

你能做什么:超越leading order的新的解决方案和新的挑战

Yi Pang, Robert J. Saskowski

AI总结 本文探讨了利用T对偶性和U对偶性生成高导数修正解的新方法,以及非微扰效应带来的挑战。

Comments 14 pages, 3 figures; essay written for the Gravity Research Foundation 2026 Awards for Essays on Gravitation

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Journal ref
Universe 2026, 12(6), 167
AI中文摘要

弦理论自然表现出双重性,这导致了低能有效描述中的隐藏对称性,这些对称性已被广泛用于生成超引力解。我们回顾了利用来自T对偶性的隐藏对称性生成高导数修正解的最新进展,以及将这一范式扩展到来自U对偶性的隐藏对称性时所遇到的非微扰效应问题。

英文摘要

String theories naturally exhibit dualities that lead to hidden symmetries in the low-energy effective description, which have been used to great effect to generate supergravity solutions. We review recent progress in using hidden symmetries arising from T-duality to generate higher-derivative-corrected solutions, as well as the problems that arise from non-perturbative effects when extending this paradigm to hidden symmetries arising from U-duality.

2502.03942 2026-06-10 stat.ME

A framework for joint assessment of a terminal event and a score existing only in the absence of the terminal event

终端事件和其不存在时的评分联合评估框架

Klaus Kähler Holst, Andreas Nordland, Julie Funch Furberg, Lars Holm Damgaard, Christian Bressen Pipper

AI总结 本文提出一种框架,用于同时评估终端事件和在终端事件不存在时存在的评分,利用半参数统计方法估计风险和评分,并通过闭合检验程序验证治疗效果。

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AI中文摘要

在易感人群中进行随机对照试验的数据分析需要特别关注,当通过测量疾病阶段或活动的评分以及终端事件的发生来评估治疗效果时。实际上,由于评分在终端事件后不再有临床意义,无法将疾病评分与终端事件分开。本文提出同时评估终端事件和在终端事件不存在时的评分。我们的方法基于自然的数据生成机制,尊重疾病评分在终端事件之后不存在的事实。我们使用现代半参数统计方法,提供稳健且高效的估计,以估计终端事件的风险和在预指定时间点无终端事件时的预期疾病评分。我们还利用估计量的联合渐近行为,开发一种强大的闭合检验程序,用于确认性评估终端事件的发生和在终端事件不存在时的评分水平。通过模拟研究和对实际试验的分析来评估性能。

英文摘要

Analysis of data from randomized controlled trials in vulnerable populations requires special attention when assessing treatment effect by a score measuring, e.g., disease stage or activity together with onset of prevalent terminal events. In reality, it is impossible to disentangle a disease score from the terminal event, since the score is not clinically meaningful after this event. In this work, we propose to assess treatment interventions simultaneously on the terminal event and the disease score in the absence of a terminal event. Our proposal is based on a natural data-generating mechanism, respecting that a disease score does not exist beyond the terminal event. We use modern semi-parametric statistical methods to provide robust and efficient estimation of the risk of terminal event and expected disease score conditional on no terminal event at a pre-specified landmark time. We also use the simultaneous asymptotic behaviour of our estimators to develop a powerful closed testing procedure for confirmatory assessment of treatment effect on both onset of terminal event and level of disease score in the absence of a terminal event. A simulation study mimicking a large-scale outcome trial in chronic kidney patients as well as an analysis of that trial is provided to assess performance.

2603.25378 2026-06-10 cs.DC

PRISM: Dynamic Primitive-Based Forecasting for Large-Scale GPU Cluster Workloads

PRISM:面向大规模GPU集群工作负载的动态基本单元预测

Xin Wu, Fei Teng, Xingwang Li, Bin Zheng, Qiang Duan

AI总结 PRISM通过结合字典驱动的时间分解与自适应频谱细化,为大规模GPU集群提供动态预测,显著减少突发阶段误差,提升AI平台资源管理效率。

Comments Accepted by DAC'26

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Journal ref
979-8-4007-2254-7/2026/07
AI中文摘要

准确预测GPU工作负载对于AI基础设施至关重要,能够实现高效的调度、资源分配和功率管理。现代工作负载高度波动、多周期性和异构性,使传统预测器难以应对。我们提出PRISM,一种基于基本单元的组合预测框架,结合字典驱动的时间分解与自适应频谱细化。这种双表示方法在不同GPU任务中提取稳定且可解释的工作负载特征。在大规模生产轨迹上评估,PRISM取得最佳结果。它显著减少了突发阶段误差,提供了一个稳健且架构感知的基础,用于GPU赋能的AI平台动态资源管理。

英文摘要

Accurately forecasting GPU workloads is essential for AI infrastructure, enabling efficient scheduling, resource allocation, and power management. Modern workloads are highly volatile, multiple periodicity, and heterogeneous, making them challenging for traditional predictors. We propose PRISM, a primitive-based compositional forecasting framework combining dictionary-driven temporal decomposition with adaptive spectral refinement. This dual representation extracts stable, interpretable workload signatures across diverse GPU jobs. Evaluated on large-scale production traces, PRISM achieves state-of-the-art results. It significantly reduces burst-phase errors, providing a robust, architecture-aware foundation for dynamic resource management in GPU-powered AI platforms.