Public Seminar of RPg Student:- Evidence of Wave Dark Matter Granulation?
Cold Dark Matter (CDM) are massive slowly moving particles which can successfully predict the large-scale structure of the Universe. However, CDM predicts a sharply rising mass density towards dwarf galaxies centre while we observe a shallow core in dwarf galaxies instead. CDM also predicts much more low-mass halos and consequently forming many low mass galaxies around a massive galaxy. However, we only observe a handful of them. Wave dark matter (psiDM) are very light particles (m ∼ 10^-22 eV) behaving like a wave in large-scale structures. PsiDM can resolve the two problems in CDM by forming soliton cores in galaxies and can suppress formation of small-scale structure and dwarf galaxies. PsiDM simulations by Schive et al. 2014 shows the formation of clumpy and granular structures inside haloes, and the signal can be probed by gravitational lensing in small-scale perturbation of magnifications. In this seminar, the speaker will demonstrate how to find observational evidence for psiDM granulation in galaxy cluster, the most powerful gravitational lenses.
講者：Ho Cheung CHAN(香港大學)