Extreme Mass Ratio Inspirals (EMRIs) present one of the key challenges in the data analysis of future data from the Laser Interferometer Space Antenna (LISA). Their long signal duration and the large number of harmonics make the search and parameter estimation of these sources particularly challenging. There are two main challenges associated with EMRI data analysis: the size of the posterior...
The Laser Interferometer Space Antenna is expected to observe numerous gravitational-wave sources in the mHz band. One promising source class are extreme mass ratio inspirals (EMRIs) of a stellar-mass compact object into a massive black hole (MBH). Accurate EMRI waveforms are essential for data analysis, but this is challenging to achieve due to the need to accurately track the phasing of...
The search for EMRIs is hindered by two main problems, the extremely
compact posterior and the degenerate parameter space with numerous
secondary peaks. This talk addresses the former by demonstrating a
complete search pipeline for stellar-mass binary inspirals; these systems
exhibit similarly compact posteriors. While the stellar-origin binaries
are an important LISA source in their own...
Extreme Mass Ratio Inspirals (EMRIs) are compact binary systems characterized by very small mass ratios (between 10⁻⁹ and 10⁻⁴), and they represent one of the primary gravitational wave (GW) sources for the forthcoming Laser Interferometer Space Antenna (LISA).
In the standard formation scenario, EMRIs originate in dense nuclear star clusters when a compact object is captured by a central...
Quasi-periodic eruptions (QPEs) are intense repeating soft X-ray bursts with recurrence times about a few hours to a few days from galactic nuclei. More and more analyses show that QPEs are the result of collisions between an EMRI and an accretion disk around a supermassive black hole (SMBH) in galactic nuclei (EMRI+disk model). In this talk, I will first review exisisting QPE observations and...
I will present a brief overview of the state-of-the-art in the topic of environmental effects for gas embedded EMRI systems, focusing on the potential and the challenges of extracting GW phase shifts from realistic signals. I will demonstrate how pushing the modelling of EMRI interaction with the gas medium beyond the commonly adopted migration torque and dynamical friction prescriptions can...
The upcoming LISA observatory will measure parameters of sources like EMRIs with exquisite precision, providing a unique avenue to test General Relativity (GR) and the matter-rich environment in galactic centers. Such "beyond-vacuum-GR" effects modify the inspiral, and if neglected from the analysis, can significantly bias ($\geq10\sigma$) parameter recovery as shown by previous studies. Yet,...
Multiple detections of extreme mass ratio inspirals (EMRIs) offer a unique opportunity to probe the population of massive black holes (MBHs). Maximizing the scientific potential of these observations requires a robust inference framework capable of handling computational challenges in likelihood evaluation and observational biases. In this work, we present a Bayesian hierarchical inference...
Extreme Mass Ratio Inspirals (EMRIs) are key observational targets for the Laser Interferometer Space Antenna (LISA) mission. Unresolvable EMRI signals contribute to the formation of a gravitational wave background (GWB).
Characterizing the statistical features of the GWB from EMRIs is of great importance, as EMRIs will ubiquitously affect large segments of the inference scheme.
In this...
EMRIs are long-lived signals with a frequency profile which may occupy the complete LISA band. On top of that, LISA is going to be signal dominated, with many different signatures overlapping in time and in frequency, while at the same time the instrumental noise which will not be completely known a-priori. In this talk, I will describe the usage of heavier-tailed likelihoods for the detection...
We present an innovative search method for gravitational wave signals from EMRIs. With the precise identification of the signal, we are able to compute the posterior distribution of EMRI signals. This leads the path to the global fit of EMRI signals overlapping with other sources of gravitational wave signals.
LISA data analysis poses many challenges.
The presence of persistent, long-lived, and overlapping sources in the data stream requires
a global fit to all the parameters of all the source models simultaneously.
The number and variety of signals, together with the dimensionality of the parameter space, call for large computational resources and extremely optimized pipelines capable of...
I am going to talk about the possibilities of finding an optimal representation for the EMRI waveform. We can follow the idea of the singular value decomposition (or similar methods, such as principle component analysis (PCA)), when we project the data on the new basis along the direction which are more representative of the data. In this way the dimensions that do not contribute much to...
The Laser Interferometer Space Antenna is expected to observe numerous gravitational-wave sources in the mHz band. One promising source class are extreme mass ratio inspirals (EMRIs) of a stellar-mass compact object into a massive black hole (MBH). Accurate EMRI waveforms are essential for data analysis, but this is challenging to achieve due to the need to accurately track the phasing of...
