The HST large programme on NGC 6752 - III. Detection of the peak of the white dwarf luminosity function
Abstract
We report on the white dwarf (WD) cooling sequence of the old globular cluster NGC 6752, which is chemically complex and hosts a blue horizontal branch. This is one of the last globular cluster WD cooling sequences accessible to imaging by the Hubble Space Telescope. Our photometry and completeness tests show that we have reached the peak of the luminosity function of the WD cooling sequence, at a magnitude mF606W = 29.4 ± 0.1, which is consistent with a formal age of ∼14 Gyr. This age is also consistent with the age from fits to the main-sequence turn-off (13-14 Gyr), reinforcing our conclusion that we observe the expected accumulation of WDs along the cooling sequence.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- September 2019
- DOI:
- 10.1093/mnras/stz1968
- arXiv:
- arXiv:1907.06300
- Bibcode:
- 2019MNRAS.488.3857B
- Keywords:
-
- white dwarfs;
- globular clusters: individual: NGC 6752;
- Astrophysics - Solar and Stellar Astrophysics;
- Astrophysics - Astrophysics of Galaxies
- E-Print:
- 10 pages, 1 table, 5 figures (3 in low resolution). Accepted for publication in MNRAS on 2019, July 12. Associated RGB-cube-WCS-fits file at https://web.oapd.inaf.it/bedin/files/PAPERs_eMATERIALs/NGC6752_III/NGC6752_RGB_WCS.fits.bz2