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The nature of absorption-selected galaxies and their connection to the general galaxy population have been open issues for more than three decades, with little information available on their gas properties. Here we show, using detections of carbon monoxide (CO) emission with the Atacama Large Millimeter/submillimeter Array (ALMA), that five of seven high-metallicity, absorption-selected galaxies at intermediate redshifts, $z approx 0.5-0.8$, have large molecular gas masses, $M_{rm Mol} approx (0.6 - 8.2) times 10^{10} : {rm M}_odot$ and high molecular gas fractions ($f_{rm Mol} equiv : M_{rm Mol}/(M_ast + M_{rm Mol}) approx 0.29-0.87)$. Their modest star formation rates (SFRs), $approx (0.3-9.5) : {rm M}_odot$ yr$^{-1}$, then imply long gas depletion timescales, $approx (3 - 120)$ Gyr. The high-metallicity absorption-selected galaxies at $z approx 0.5-0.8$ appear distinct from populations of star-forming galaxies at both $z approx 1.3-2.5$, during the peak of star formation activity in the Universe, and lower redshifts, $z lesssim 0.05$. Their relatively low SFRs, despite the large molecular gas reservoirs, may indicate a transition in the nature of star formation at intermediate redshifts, $z approx 0.7$.
We present the stellar population and ionized-gas outflow properties of ultra-luminous IR galaxies (ULIRGs) at $z=$ 0.1-1.0, which are selected from AKARI FIR all-sky survey. We construct a catalog of 1077 ULIRGs to examine feedback effect after majo
Massive quiescent compact galaxies have been discovered at high redshifts, associated with rapid compaction and cessation of star formation (SF). In this work we set out to quantify the time-scales in which SF is quenched in compact galaxies at inter
A decade of study has established that the molecular gas properties of star-forming galaxies follow coherent scaling relations out to z~3, suggesting remarkable regularity of the interplay between molecular gas, star formation, and stellar growth. Pa
We present the first study of large-scale bars in clusters at intermediate redshifts (z=0.4-0.8). We compare the properties of the bars and their host galaxies in the clusters with those of a field sample in the same redshift range. We use a sample o
We study properties of the host galaxies of 15 hard X-ray selected type-2 active galactic nuclei (AGNs) at intermediate redshifts (0.05$<z<$0.6) detected in $ASCA$ surveys. The absorption corrected hard X-ray luminosities $L_{rm 2-10 keV}$ range from