We show that the existence of clouds of ultralight particles surrounding black holes during their cosmological history as members of a binary system can leave a measurable imprint on the distribution of masses and orbital eccentricities observable with future gravitational-wave detectors. Notably, we find that for nonprecessing binaries with chirp masses ${\cal M} \lesssim 10\,M_\odot$, formed exclusively in isolation, larger-than-expected values of the eccentricity, i.e. $e\gtrsim 10^{-2}$ at gravitational-wave frequencies $f_{\rm GW} \simeq 10^{-2}\,$Hz, would provide tantalizing evidence for a new particle of mass between $[0.5,2.5] \times 10^{-12}\,$eV in nature. The predicted evolution of the eccentricity can also drastically affect the in-band phase evolution and peak frequency. These results constitute unique signatures of boson clouds of ultralight particles in the dynamics of binary black holes, which will be readily accessible with the Laser Interferometer Space Antenna, as well as future mid-band and Deci-hertz detectors.
Common Envelope Evolution of Ultralight Boson Clouds
International Centre for Theoretical Physics Asia-Pacific, University of Chinese Academy of Sciences（国际理论物理中心亚太分中心，中国科学院大学）；Department of Astronomy, Tsinghua University（清华大学天文系）；Taiji Laboratory for Gravitational Wave Universe (Beijing/Hangzhou), University of Chinese Academy of Sciences（太极引力波宇宙实验室（北京/杭州），中国科学院大学）
We derive in detail the orbital period loss of a compact binary system in presence of a fifth force and radiation of ultralight particles for a general eccentric Keplerian orbit. We obtain constraints on fifth force strength $α\lesssim 1.11\times 10^{-3}$ from the orbital period decay of compact binary systems. We derive constraints on the gauge coupling of ultralight scalar $(g_S\lesssim 3.06\times 10^{-20})$ and vector $(g_V\lesssim 2.29\times 10^{-20})$ particles from orbital period loss and the constraints get stronger in presence of a fifth force $(α=0.9)$. In addition, we also obtain con…
In the presence of an ultralight bosonic field, spinning black holes are unstable to superradiance. The rotational energy of the black hole is converted into a non-axisymmetric, oscillating boson cloud which dissipates through the emission of nearly monochromatic gravitational radiation. Thus, gravitational wave observations by ground- or space-based detectors can be used to probe the existence of dark particles weakly coupled to the Standard Model. In this work, we focus on massive vector bosons, which grow much faster through superradiance, and produce significantly stronger gravitational wa…
Ultralight bosons can be abundantly produced through superradiance process by a spinning black hole and form a bound state with hydrogen-like spectrum. We show that such a "gravitational atom" typically possesses anomalously large mass quadrupole and leads to significant orbital precession when it forms an eccentric binary with a second compact object. Dynamically formed black hole binaries or pulsar-black hole binaries are typically eccentric during their early inspirals. We show that the large orbital precession can generate distinct and observable signature in their gravitational wave or pu…
Nonlinearities in a realistic axion field potential may play an important role in the cosmological dynamics. In this paper we use the Boltzmann code CLASS to solve the background and linear perturbations evolution of an axion field and contrast our results with those of CDM and the free axion case. We conclude that there is a slight delay in the onset of the axion field oscillations when nonlinearities in the axion potential are taken into account. Besides, we identify a tachyonic instability of linear modes resulting in the presence of a bump in the power spectrum at small scales. Some commen…
The process of superradiance can extract angular momentum and energy from astrophysical black holes (BHs) to populate gravitationally-bound states with an exponentially large number of light bosons. We analytically calculate superradiant growth rates for vectors around rotating BHs in the regime where the vector Compton wavelength is much larger than the BH size. Spin-1 bound states have superradiance times as short as a second around stellar BHs, growing up to a thou- sand times faster than their spin-0 counterparts. The fast rates allow us to use measurements of rapidly spinning BHs in X-ray…
We study the gravitational-wave (GW) signatures of clouds of ultralight bosons around black holes (BHs) in binary inspirals. These clouds, which are formed via superradiance instabilities for rapidly rotating BHs, produce distinct effects in the population of BH masses and spins, and a continuous monochromatic GW signal. We show that the presence of a binary companion greatly enriches the dynamical evolution of the system, most remarkably through the existence of resonant transitions between the growing and decaying modes of the cloud (analogous to Rabi oscillations in atomic physics). These r…
Ultralight Boson Ionization from Comparable-Mass Binaries
Shanghai Jiao Tong University（上海交通大学）；CENTRA, Departamento de Física, Instituto Superior Técnico – IST, Universidade de Lisboa – UL（里斯本大学高级技术学院物理系CENTRA中心）；Tsung-Dao Lee Institute, Shanghai Jiao Tong University（上海交通大学李政道研究所）；Dipartimento di Fisica, Sapienza Università di Roma & INFN, Sezione di Roma（罗马第一大学物理系及罗马INFN分部）；Walter Burke Institute for Theoretical Physics, California Institute of Technology（加州理工学院沃尔特·伯克理论物理研究所）
Sensitivity of binary pulsar timing to spin-0 and spin-1 ultralight dark matter
Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales（布宜诺斯艾利斯大学，理学院）；CONICET, Instituto de Física de Buenos Aires (IFIBA)（阿根廷国家科学研究委员会，布宜诺斯艾利斯物理研究所）
Signatures of Ultralight Dark Matter in Space-Based Laser Interferometers
University of Chinese Academy of Sciences (UCAS)（中国科学院大学）；International Center for Theoretical Physics Asia-Pacific（亚太理论物理中心）；School of Fundamental Physics and Mathematical Sciences, Hangzhou Institute for Advanced Study, UCAS（杭州高等研究院基础物理与数学科学学院）
Ultra-light bosons as dark matter has become a model of major interest in Cosmology, due to the possible imprint of a distinct signature in the cosmic structure both at the linear and non-linear scales. In this work we show that the equations of motion for density perturbations for this kind of models can be written in terms of a modified gravitational potential. Taking advantage of this parallelism, we use the MG-PICOLA code originally developed for modified gravity models to evolve the density field of axion models with and without self-interaction. Our results indicate that the quantum pote…
The Atacama Cosmology Telescope: Probing new signatures of ultralight axions with gravitational lensing
University of Pennsylvania（宾夕法尼亚大学）；King’s College London（伦敦国王学院）；Imperial College London（帝国理工学院）；Dunlap Institute for Astronomy and Astrophysics, University of Toronto（多伦多大学邓普天文学与天体物理研究所）；Canadian Institute for Theoretical Astrophysics, University of Toronto（多伦多大学加拿大理论天体物理研究所）；Cardiff University（卡迪夫大学）；Princeton University（普林斯顿大学）；University of Southern California（南加州大学）；Institute for Advanced Study（高等研究院）
Effect of ultralight dark matter on compact binary mergers
Chennai Mathematical Institute（金奈数学研究所）；CEICO, Institute of Physics of the Czech Academy of Sciences（捷克科学院物理研究所 CEICO）；Indian Institute of Technology, Gandhinagar（印度技术学院甘地纳加尔分校）；School of Physical Sciences, Indian Association for the Cultivation of Science（印度科学培养协会物理科学学院）
Ultralight bosons can affect the dynamics of spinning black holes (BHs) via superradiant instability, which can lead to a time evolution of the supermassive BH shadow. We study prospects for witnessing the superradiance-induced BH shadow evolution, considering ultralight vector and tensor fields. We introduce two observables sensitive to the shadow time-evolution: the shadow drift, and the variation in the azimuthal angle lapse associated to the photon ring autocorrelation. The two observables are shown to be highly complementary, depending on the observer's inclination angle. Focusing on the …
External Attention Transformer: A Robust AI Model for Identifying Initial Eccentricity Signatures in Binary Black Hole Events in Simulated Advanced LIGO Data
Probing ultralight bosons with LISA observations of spinning black hole mergers and follow-up searches of merger remnants
Perimeter Institute for Theoretical Physics（Perimeter理论物理研究所）；University of Waterloo（滑铁卢大学）；Max Planck Institute for Gravitational Physics (Albert Einstein Institute)（马克斯·普朗克引力物理学研究所（爱因斯坦研究所））
Eccentric or circular? A reanalysis of binary black hole gravitational wave events for orbital eccentricity signatures
Universitat de les Illes Balears（巴利阿里群岛大学）；Universität Zürich（苏黎世大学）；Max Planck Institut für Gravitationsphysik (Albert Einstein Institut)（马克斯·普朗克引力物理研究所（爱因斯坦研究所））；Institut de Ciències de l’Espai (ICE, CSIC)（空间科学研究所（加泰罗尼亚高等研究理事会））；Dutch National Institute for Subatomic Physics (Nikhef)（荷兰亚原子物理国家研究所）
Prospects for Direct Detection of Ultralight Dark Matter candidates in deci-Hz Band with IndIGO-D
Saha Institute of Nuclear Physics（萨哈核物理研究所）；Homi Bhabha National Institute（霍米·巴巴国立研究所）；International Centre for Theoretical Physics Asia-Pacific (ICTP-AP), University of Chinese Academy of Sciences (UCAS)（中国科学院大学亚太理论物理中心（ICTP-AP））；Taiji Laboratory for Gravitational Wave Universe, University of Chinese Academy of Sciences（中国科学院大学太极引力波宇宙实验室）
Orbital eccentricity is a key signature of dynamical binary black hole formation. The gravitational waves from a coalescing binary contain information about its orbital eccentricity, which may be measured if the binary retains sufficient eccentricity near merger. Dedicated waveforms are required to measure eccentricity. Several models have been put forward, and show good agreement with numerical relativity at the level of a few percent or better. However, there are multiple ways to define eccentricity for inspiralling systems, and different models internally use different definitions of eccent…
Dancing in the dark: probing Dark Matter through the dynamics of eccentric binary pulsars
Montana State University（蒙大拿州立大学）；University of Aveiro（阿威罗大学）；Gran Sasso Science Institute (GSSI)（格兰萨索科学研究所）；INFN, Laboratori Nazionali del Gran Sasso（意大利国家核物理研究所，格兰萨索国家实验室）
Orbital eccentricity in a neutron star - black hole merger
University of Birmingham（伯明翰大学）；Instituto de Física Teórica UAM/CSIC, Universidad Autónoma de Madrid（马德里自治大学理论物理研究所(UAM/CSIC)）；Max Planck Institute for Gravitational Physics (Albert Einstein Institute)（马克斯·普朗克引力物理学研究所(爱因斯坦研究所)）
Direct detection of gravitational waves from several compact binary coalescences has ushered in a new era of astronomy. It has opened up the possibility of detecting ultralight bosons, predicted by extensions of the Standard Model, from their gravitational signatures. This is of particular interest as some of these hypothetical particles could be components of dark matter that are expected to interact very weakly with Standard Model particles, if at all, but they would gravitate as usual. Ultralight bosons can trigger superradiant instabilities of rotating black holes and form bosonic clouds t…
Gravitational waves (GWs) are an exciting new probe of physics beyond the standard models of gravity and particle physics. One interesting possibility is provided by the so-called "gravitational atom," wherein a superradiant instability spontaneously forms a cloud of ultralight bosons around a rotating black hole. The presence of these boson clouds affects the dynamics of black hole binary inspirals and their associated GW signals. In this Letter, we show that the binary companion can induce transitions between bound and unbound states of the cloud, effectively "ionizing" it, analogous to the …
We study observational consequences of the model for dark energy proposed in [1] (Aoki et al., Phys.Rev. D97 (2018) no.4, 043517). We assume our universe has been created by bubble nucleation, and consider quantum fluctuations of an ultralight scalar field. Residual effects of fluctuations generated in an ancestor vacuum (de Sitter space in which the bubble was formed) is interpreted as dark energy. Its equation of state parameter w(z) has a characteristic form, approaching -1 in the future, but -1/3 in the past. A novel feature of our model is that dark energy effectively increases the magnit…
The origin of black hole mergers discovered by the LIGO and Virgo gravitational-wave observatories is currently unknown. GW190521 is the heaviest black hole merger detected so far. Its observed high mass and possible spin-induced orbital precession could arise from the binary having formed following a close encounter. An observational signature of close encounters is eccentric binary orbit; however, this feature is currently difficult to identify due to the lack of suitable gravitational waveforms. No eccentric merger has been previously found. Here we report 611 numerical relativity simulatio…
Observable signature of magnetic tidal coupling in hierarchical triple systems
Università di Perugia（佩鲁贾大学）；I.N.F.N. Sezione di Perugia（意大利国家核物理研究所佩鲁贾分部）；Niels Bohr Institute, Copenhagen University（哥本哈根大学尼尔斯·玻尔研究所）；Nordita, KTH Royal Institute of Technology and Stockholm University（诺迪塔，皇家理工学院与斯德哥尔摩大学）
The direct detection of gravitational waves offers an exciting new window onto our Universe. At the same time, multiple observational evidence and theoretical considerations motivate the presence of physics beyond the Standard Model. In this thesis, we explore new ways of probing particle physics in the era of gravitational-wave astronomy. We focus on the signatures of ultralight bosons on the gravitational waves emitted by binary systems, demonstrating how binary black holes are novel detectors of this class of dark matter. We also discuss probes of other types of new physics through their fi…
An Accurate Modeling of Nano-hertz Gravitational Wave Signal from Eccentric Supermassive Binary Black Holes: An Essential Step Toward a Robust Discovery
Constraining initial orbital eccentricity of inspiral-dominated gravitational-wave events with an analytic approximant
The Chinese University of Hong Kong（香港中文大学）；Tata Institute of Fundamental Research（塔塔基础研究所）；Nikhef—National Institute for Subatomic Physics（NIKHEF-国家亚原子物理研究所）；KU Leuven（荷语鲁汶大学）；The Inter-University Centre for Astronomy and Astrophysics（大学间天文学与天体物理学中心）
Ultralight bosons and axion-like particles appear naturally in different scenarios and could solve some long-standing puzzles. Their detection is challenging, and all direct methods hinge on unknown couplings to the Standard Model of particle physics. However, the universal coupling to gravity provides model-independent signatures for these fields. We explore here the superradiant instability of spinning black holes triggered in the presence of such fields. The instability taps angular momentum from and limits the maximum spin of astrophysical black holes. We compute, for the first time, the s…
Black-hole - neutron-star mergers: new numerical-relativity simulations and multipolar effective-one-body model with spin precession and eccentricity
Universitat de les Illes Balears（巴利阿里群岛大学）；Friedrich-Schiller-Universität Jena（耶拿弗里德里希·席勒大学）；The Pennsylvania State University（宾夕法尼亚州立大学）；University of California, Berkeley（加州大学伯克利分校）；Università di Bologna（博洛尼亚大学）
Gravitational-Wave Signatures of Highly Eccentric Stellar-Mass Binary Black Holes in Galactic Nuclei
Monash University（莫纳什大学）；OzGrav: Australian Research Council Centre of Excellence for Gravitational Wave Discovery（澳大利亚研究委员会引力波发现卓越中心）；Department of Applied Mathematics and Theoretical Physics, Cambridge（剑桥大学应用数学与理论物理系）；Kavli Institute for Cosmology Cambridge（卡弗里宇宙学剑桥研究所）；H. H. Wills Physics Laboratory, University of Bristol（布里斯托大学H.H.威尔斯物理实验室）；Gravity Exploration Institute, School of Physics and Astronomy, Cardiff University（卡迪夫大学物理与天文学重力探索研究所）；Departamento de Astronomía, Facultad Ciencias Físicas y Matemáticas, Universidad de Concepción（康塞普西翁大学物理与数学科学学院天文学系）；National Institute for Nuclear Physics – INFN, Sezione di Trieste（意大利国家核物理研究所的里雅斯特分部）
We study the dynamical signatures of black hole (BH) and neutron star (NS) binary mergers via Lidov-Kozai oscillations induced by tertiary companions in hierarchical triple systems. For each type of binaries (BH-BH and BH-NS), we explore a wide range of binary/triple parameters that lead to binary mergers, and determine the distributions of eccentricity ($e_\mathrm{m}$) and spin-orbit misalignment angle ($θ_\rm {sl}^\rm f$) when the binary enters the LIGO/VIRGO band. We use the double-averaged (over both orbits) and single-averaged (over the inner orbit) secular equations, as well as N-body in…
Compact object binaries formed from dynamics interactions will generically have non-zero orbital eccentricity. The gravitational waves from such binaries can change drastically depending on how large the eccentricity is, ranging from emitted in small a subset of orbital harmonics at low eccentricities, to being concentrated into intense bursts of radiation from each pericenter passage at large eccentricities. Gravitational waves from such highly eccentric binaries present themselves an intriguing systems for probing fundamental physics, but also present interesting challenges in terms of detec…
