Impact of photometric variability on age and mass determination in young stellar objects: the case of the Orion Nebula Cluster
Date Issued
2017
Author(s)
Abstract
Very young stars, like the Orion Nebula Cluster (ONC) members analysed in the present study, exhibit photometric variability with a wide range of amplitudes. Such a prominent variability reflects in the inferred values of stellar colours and luminosities and, in turn, in the inferred stellar ages and masses. In this study, we measure the amplitudes of the photometric variability in V, R and I optical bands of a sample of 346 ONC members. We use these measurements to investigate how this variability affects the inferred masses and ages and whether it alone can account for the age spread among ONC members reported by earlier studies. We make use of colour-magnitude and Hertzprung-Russell (HR) diagrams. We find that members that show periodic and smooth photometric rotational modulation have masses and ages that are unaffected by variability when theoretical isochrones and evolutionary mass tracks are used in either colour-magnitude or HR diagrams. On the other hand, members with periodic but very scattered photometric rotational modulation and non-periodic members have masses and ages that are significantly affected. Moreover, using HR diagrams, we find that the observed I-band photometric variability can take account of only a fraction (∼50 per cent) of the inferred age spread, whereas the V-band photometric variability is large enough to mask any age spread.
Volume
468
Issue
1
Start page
931
Issn Identifier
0035-8711
Ads BibCode
2017MNRAS.468..931M
Rights
open.access
File(s)![Thumbnail Image]()
Loading...
Name
stx230.pdf
Description
PDF editoriale
Size
1.84 MB
Format
Adobe PDF
Checksum (MD5)
adcb054d039ddec4158f2479b2bdbe60