20.500.12556/RUL-176506 JWST photometry of globular cluster populations in MACS0417.5−1154 Deep JWST imaging of the massive galaxy cluster MACS0417.5−1154, at redshift z = 0.443, reveals a huge population of globular clusters (GCs) and ultracompact dwarfs (UCDs) primarily distributed around its single central giant brightest cluster galaxy (BCG). We present Near-Infrared Camera (NIRCam)/short-wavelength channel photometry of the GC system in four bands (F090W, F115W, F150W, and F200W). The spatial distribution of the system matches well in radial and ellipticity profile with the high elongation (b/a ≃ 0.5) of the BCG halo light. The total GC population within MACS0417 is estimated to be near 1.5 × 10$^5$, similar to the systems in Abell 2744, Coma, and other galaxy clusters with comparable masses. With similar results for GC photometry in hand from other lensing clusters at a range of redshifts, it is now possible to trace, on purely observational grounds, the luminosity evolution of GC systems over many gigayears of lookback time, as seen through their color–magnitude diagrams. We show this sequence for five systems reaching lookback times of more than 7 Gyr. A systematic change in the GC/UCD sequence with lookback time is clearly visible, near what is expected for age-fading of a simple stellar population with time. Lastly, we evaluate the effectiveness of the various JWST NIRCam filters for broadband photometry of GC systems as a function of redshift as an aid to planning further studies. astrophysics galaxy clusters astrofizika jate galaksij true false true Angleški jezik Slovenski jezik Članek v reviji 2025-12-02 14:14:31 2025-12-02 14:14:32 2025-12-22 03:54:45 0000-00-00 00:00:00 2025 0 0 13 str. no. 2 Vol. 993 Nov. 2025 0000-00-00 Zaloznikova Objavljeno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 524.8 1538-4357 10.3847/1538-4357/ae073f 259612163 Harris_2025_ApJ_993_210.pdf Harris_2025_ApJ_993_210.pdf 1 7A071A5A5F7D8369D604A02808C4B7AA 20023f74e15de6d76c69d7392376f36ada54fef6345c34cc6334d49ac77f0764 9d1c4ea6-cf84-11f0-9328-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=222882 https://iopscience.iop.org/article/10.3847/1538-4357/ae073f 0 a4b90b5e-cf84-11f0-9328-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=222883 Fakulteta za matematiko in fiziko 0 0 0