EDP Sciences
Free Access
Erratum
This article is an erratum for: [this article]

Issue
A&A
Volume 587, March 2016
Article Number C3
Number of page(s) 1
Section Galactic structure, stellar clusters and populations
DOI https://doi.org/10.1051/0004-6361/201220824e
Published online 19 February 2016

Equation (9), representing the phase φ(t) at time t of a periodic variable undergoing a period change, is erroneous. This equation should instead read (1)where NE(t) is the number of cycles elapsed at time t since a reference epoch E. The quantity NE(t) for a constant rate of period change is given by (2)

where β is the period change rate and P0 is the period at the epoch E.

Consequently our derived period change rate for the RR Lyrae star V2 in NGC 7492 is wrong. Repeating the analysis with the correct equations, we obtain P0 = 0.412119 d at epoch E = 2 453 284.2652 d and β ≈ 2.6 × 10-7 d d-1 (or β ≈ 95 d Myr-1). We find that the phased light curve for V2 using these new parameters (and equations) is further improved.


© ESO, 2016

Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.

Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.

Initial download of the metrics may take a while.