학술논문
JWST NIRCam Photometry: A Study of Globular Clusters Surrounding Bright Elliptical Galaxy VV 191a at z=0.0513
Document Type
Working Paper
Author
Berkheimer, Jessica M.; Carleton, Timothy; Windhorst, Rogier A.; Keel, William C.; Holwerda, Benne W.; Nonino, Mario; Cohen, Seth H.; Jansen, Rolf A.; Coe, Dan; Conselice, Christopher J.; Driver, Simon P.; Frye, Brenda L.; Grogin, Norman A.; Koekemoer, Anton M.; Lucas, Ray; Marshall, Madeline A.; Pirzkal, Nor; Robertson, Clayton; Robotham, Aaron; Ryan Jr., Russell E.; Smith, Brent M.; Summers, Jake; Tompkins, Scott; Willmer, Christopher N. A.; Yan, Haojing
Source
Subject
Language
Abstract
James Webb Space Telescope NIRCam images have revealed 154 reliable globular cluster (GC) candidates around the $z = 0.0513$ elliptical galaxy VV~191a after subtracting 34 likely interlopers from background galaxies inside our search area. NIRCam broadband observations are made at 0.9-4.5 $\mu$m using the F090W, F150W, F356W, and F444W filters. Using PSF-matched photometry, the data are analyzed to present color-magnitude diagrams (CMDs) and color distributions that suggest a relatively uniform population of GCs, except for small fractions of reddest (5-8%) and bluest (2-4%) outliers. GC models in the F090W vs. (F090-F150W) diagram fit the NIRCam data well and show that the majority of GCs detected have a mass of approximately $\sim$$10^{6.5}$$M_{\odot}$, with metallicities [Fe/H] spanning the typical range expected for GCs (-2.5$\le$ [Fe/H]$\le$ 0.5). However, the models predict $\sim$0.3-0.4 mag bluer (F356W-F444W) colors than the NIRCam data for a reasonable range of GC ages, metallicities, and reddening. Although our data does not quite reach the luminosity function turnover, the measured luminosity function is consistent with previous measurements, suggesting an estimated peak at $m_{\rm AB}$$\sim$-9.4 mag, $\pm$0.2 mag in the F090W filter.
Comment: 11 pages, 7 figures
Comment: 11 pages, 7 figures