今後のセミナー
5月のセミナー
発表者
Maxime Paillassa
日程/場所
5月24日(水)13:30-@ES635
題名
Source detection and deblending: from classical algorithms to machine learning.
概要
In this C-seminar, I will present source detection techniques for wide-field imaging surveys.
I will first review how astronomical images form and the classical approaches for source detection.
Then, we will see how those methods can be naturally extended with machine learning techniques.
Finally, after reviewing some applications of machine learning for source detection and deblending,
I will present our work about blend identification for HSC images.
発表者
Santiago Jaraba (IFT UAM-CSIC)
日程/場所
5月17日(水)13:30-@ES635
題名
Stochastic gravitational wave background constraints from Gaia DR3 astrometry
概要
astrometric surveys can be used to constrain the stochastic gravitational wave background (SGWB) at very low frequencies.
The European Space Agency’s (ESA) Gaia mission, launched in 2013 and with a recent data release (DR3) in 2022, shows great
potential for this purpose. In this talk, I will review the formalism that relates astrometry to gravitational waves and
talk about a recent work in which we used Gaia DR3 to set constraints on the SGWB amplitude. I will also comment on previous
works which computed similar constraints and discuss the potential of future Gaia data releases to impose tighter bounds.
4月のセミナー
発表者
Xiaolin LIU
日程/場所
4月26日(水)13:30-@ES635
題名
Study on the gravitational waves from elliptical two-body system with spin-precessing effects based on effective-one-body formalism
概要
Binary systems are the most common sources of gravitational waves in the universe. In the detection and data processing of gravitational waves, modeling of gravitational wave sources is crucial. Binary black hole systems have very complex dynamical properties. For a long time, mainstream gravitational wave models only supported the computation of non-memory effect gravitational waves from circular orbit binary black hole systems. With the improvement in sensitivity of future gravitational wave detectors and the launch of space detector projects, there will be an increasing demand for gravitational wave templates with a larger parameter range and higher accuracy. In this work, we computed the orbital dynamics and decomposed waveform that simultaneously support eccentricity and spin precession in the effective-one-body formalism with second-order post-Newtonian accuracy. We then tested this new model and compared its performance in circular orbit situations, and discussed the parameter estimation bias that would result from ignoring this effect in future O4 observations through simulated parameter estimation.