UZH-Logo

Maintenance Infos

Galactic-center S stars as a prospective test of the Einstein equivalence principle


Angélil, R; Saha, P (2011). Galactic-center S stars as a prospective test of the Einstein equivalence principle. Astrophysical Journal Letters, 734(1):L19.

Abstract

The S stars in the Galactic-center region are found to be on near-perfect Keplerian orbits around presumably a supermassive black hole, with periods of 15-50 yr. Since these stars reach a few percent of light speed at pericenter, various relativistic effects are expected and have been discussed in the literature. We argue that an elegant test of the Einstein equivalence principle should be possible with existing instruments, through spectroscopic monitoring of an S star concentrated during the months around pericenter, supplemented with an already-adequate astrometric determination of the inclination. In essence, the spectrum of an S star can be considered a heterogeneous ensemble of clocks in a freely falling frame, which near pericenter is moving at relativistic speeds.

The S stars in the Galactic-center region are found to be on near-perfect Keplerian orbits around presumably a supermassive black hole, with periods of 15-50 yr. Since these stars reach a few percent of light speed at pericenter, various relativistic effects are expected and have been discussed in the literature. We argue that an elegant test of the Einstein equivalence principle should be possible with existing instruments, through spectroscopic monitoring of an S star concentrated during the months around pericenter, supplemented with an already-adequate astrometric determination of the inclination. In essence, the spectrum of an S star can be considered a heterogeneous ensemble of clocks in a freely falling frame, which near pericenter is moving at relativistic speeds.

Citations

8 citations in Web of Science®
2 citations in Scopus®
Google Scholar™

Altmetrics

Downloads

23 downloads since deposited on 18 Feb 2012
6 downloads since 12 months
Detailed statistics

Additional indexing

Item Type:Journal Article, refereed, original work
Communities & Collections:07 Faculty of Science > Institute for Computational Science
Dewey Decimal Classification:530 Physics
Language:English
Date:June 2011
Deposited On:18 Feb 2012 14:17
Last Modified:05 Apr 2016 14:55
Publisher:Institute of Physics Publishing
ISSN:0004-637X (P) 1538-4357 (E)
Publisher DOI:10.1088/2041-8205/734/1/L19
Related URLs:http://arxiv.org/abs/1105.0918
Permanent URL: http://doi.org/10.5167/uzh-48282

Download

[img]
Preview
Content: Accepted Version
Filetype: PDF
Size: 144kB
View at publisher

TrendTerms

TrendTerms displays relevant terms of the abstract of this publication and related documents on a map. The terms and their relations were extracted from ZORA using word statistics. Their timelines are taken from ZORA as well. The bubble size of a term is proportional to the number of documents where the term occurs. Red, orange, yellow and green colors are used for terms that occur in the current document; red indicates high interlinkedness of a term with other terms, orange, yellow and green decreasing interlinkedness. Blue is used for terms that have a relation with the terms in this document, but occur in other documents.
You can navigate and zoom the map. Mouse-hovering a term displays its timeline, clicking it yields the associated documents.

Author Collaborations