سخنران: محمد آخشیک (دانشگاه کنتیکت، آمریکا)
پانزدهم دی ماه ۱۳۹۹
ساعت ۱۷ الی ۱۸
 

In this talk, I will first discuss the methodology behind the new code, 'requiem2d', a Bayesian framework thatcombinesHST 2D grism spectroscopy with HST and Spitzer photometric data to constrain the spatially resolved stellar populations and measure age and star-formation rate gradients. This code is developed for the purpose of analyzing the REQUIEM^2D Galaxy Survey, a sample of 8 strongly lensed quiescent galaxies spanning redshifts of z = 1.6 − 2.9 and stellar masses of log M* = 10.4 − 11.5. After briefly reviewing the sample, I will discuss the results from our REQUIEM^2D pilot target, MRG-S0851, a gravitationally lensed quintuply imaged massive compact red galaxy at z=1.9. Using our recovered ages and SFHs from the joint spectrophotometric analysis, along with trajectories in the UVJ and FUVVJ color-color diagrams, I show that MRG-S0851 is consistent with an early forming, slow quenched galaxy that is going through a centrally-concentrated rejuvenation phase. I finally discuss that using MRG-S0851 as a prototype, ~1% of massive quiescent galaxies at 1<z<2 seem to be rejuvenating.