Astrometric detection of intermediate-mass black holes at the Galactic Centre. Issue 3 (1st October 2018)

• Record Type: Journal Article
• Authors: Girma, Eden; Loeb, Abraham
• Is Part Of: Monthly notices of the Royal Astronomical Society. Volume 482:Issue 3(2019)
• Page Start: 3669
• Page End: 3677
• Publication Date: 2018-10-01
• Subjects: black hole physics -- methods: numerical -- Galaxy: centre; Astronomy -- Periodicals; Periodicals; 520.5
• DOI: 10.1093/mnras/sty2643
• Languages: English
• ISSNs: 0035-8711

Abstract

Abstract: We assess the astrometric detectability of intermediate-mass black holes populating the inner parsec of the Milky Way Galaxy. The presence of these objects induces dynamical effects on Sgr A* and the star S2, which could be detected by next generation astrometric instruments that enable microarcsec astrometry. An allowed population of ten 10 4 M⊙ intermediate-mass black holes within one parsec induces an angular shift of${\sim } 65\, \mu \rm{as\, yr}^{-1}$ on the position of Sgr A*, corresponding to a perpendicular velocity component magnitude of$1.6\, \rm{km\, s}^{-1}$ . It also induces changes in the orbit of S2 that surpass those induced by general relativity but lie within observational constraints, generating a mean angular shift in periapse and apoapse of 62 and 970 µas, respectively.