Searching for Massive Black Hole Binary candidates through periodic modulations in LSST and confirming their nature through spectroscopic follow-ups

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Ομιλητής :  
Lorenzo Bertassi (University of Milano-Biccoca, Ιταλία)
Αίθουσα :  
2ος όροφος Αίθουσα Σεμιναρίων Τμήμα Φυσικής και Online
Ημερομηνία :  

Ώρα : 

Video
Περίληψη :

Massive black hole binaries (MBHBs) are expected to be among the 
loudest gravitational wave sources detectable by pulsar timing arrays and space-borne interferometers. If accreting, MBHBs at sub-parsec 
separations (<0.01 pc) can be identified through periodic variability in their light curves. The Vera C. Rubin Observatory Legacy Survey of Space and Time (LSST), with its unprecedented wide-sky coverage, multi-band photometry, and high-cadence observations, will allow the detection of a large number of periodic MBHB candidates, which could then be validated through independent methods. Current periodicity detection methods, though, are largely optimised for quasi-sinusoidal signals, whereas the predicted light curves from MBHBs present a much richer phenomenology. In this talk, I will present a periodicity detection method based on Gaussian processes that flexibly models periodic variability independently of its specific shape. I will then introduce a spectroscopic test to distinguish photometrically selected MBHB candidates from single massive black holes with quasi-periodic continuum variability, using the response of the broad-line region (BLR).