Proper motions in globular clusters using deconvolution of HST images
Abstract
A sub-sampled deconvolution technique for crowded field photometry with the HST WFPC2 instrument was proposed by \citet{butler_2000} and applied to search for optical counterparts to pulsars in globular clusters \citep{golden_2001}. Simulations showed that the method, which takes account of the point-spread function (PSF) spatial variation, can provide better star detection and recovers the resolution lost to aberrations and poor sampling. The original emphasis was on precision photometry in crowded fields. In the present work, we have extended this technique to determine proper motions of stars in globular clusters. Actual HST images of the globular clusters, along with realistic simulations of the globular clusters, were used to benchmark the technique for astrometric accuracy. The ultimate aim is to use this dynamical data to search for intermediate-mass black holes in globular cluster cores.
- Publication:
-
Memorie della Societa Astronomica Italiana
- Pub Date:
- 2013
- DOI:
- 10.48550/arXiv.1306.0575
- arXiv:
- arXiv:1306.0575
- Bibcode:
- 2013MmSAI..84..191S
- Keywords:
-
- Proper motion;
- Deconvolution;
- Globular clusters;
- M71;
- NGC 6293-HST;
- Astrophysics - Solar and Stellar Astrophysics;
- Astrophysics - Galaxy Astrophysics
- E-Print:
- 4 pages, 5 figures, To appear in the conference proceedings "Reading the book of globular clusters with the lens of stellar evolution", Mem. S. A. It. Eds. P. Ventura, C. Charbonnel, M. Castellani and M. Di Criscienzo