相关论文: Possible Population III Remnants at Redshift 3.5

The most metal-poor, high redshift damped Lyman-alpha systems (DLAs) provide a window to study some of the first few generations of stars. In this paper, we present a novel model to investigate the chemical enrichment of the near-pristine…

The first generation of stars, Population III (Pop III), is believed to be massive, with some potentially having masses in the range 140 M$_\odot$ to 270 M$_\odot$ and capable of exploding as a pair-instability supernova (PISN). Such events…

The chemical enrichment of the early Universe is a crucial element in the formation and evolution of galaxies, and Population III (PopIII) stars must play a vital role in this process. In this study, we examine metal enrichment from massive…

Star formation from metal-free gas, the hallmark of the first generation of Population III stars, was long assumed to occur only in the very early Universe. We report the discovery of MPG-CR3 (Metal-Pristine Galaxy COSMOS Redshift 3;…

We report the discovery of three new "near-pristine" Lyman Limit Systems (LLSs), with metallicities ~1/1000 solar, at redshifts 2.6, 3.8 and 4.0, with a targeted survey at the Keck Observatory. High resolution echelle spectra of eight…

By definition, Population III stars are metal-free, and their protostellar collapse is driven by molecular hydrogen cooling in the gas-phase, leading to large characteristic masses. Population II stars with lower characteristic masses form…

It has recently become possible to measure directly the abundances of several chemical elements in a variety of environments at redshifts up to z = 5. In this review I summarise the latest observations of Lyman break galaxies, damped Lyman…

The chemical composition of the most metal-deficient stars reflects the composition of the gas from which they formed. These old stars provide crucial clues to the star formation history and the synthesis of chemical elements in the early…

We conduct a comprehensive investigation of the detectability of the first stars and their enrichment signatures in galaxy clusters. We show that the mean metallicity of outflows from objects containing these Population III (PopIII) stars…

Motivated by the recent detection of metals in different components of the high redshift universe and by the abundance ratios measured in the extremely metal-poor stars of our Galaxy, we study the nucleosynthesis constraints that this…

It is widely recognized that nucleosynthetic output of the first, Population III supernovae was a catalyst defining the character of subsequent stellar generations. Most of the work on the earliest enrichment was carried out assuming that…

We investigate the metal contents of Lyman-alpha clouds at 2.2<z<3.6 with 10^13.5<N(HI)<10^14 cm-2 using high resolution, high S/N spectra of 9 quasars obtained with the 10m Keck I telescope. Using an composite spectrum analysis technique,…

According to the leading cosmological model, a first generation of stars called Population III (PopIII), condensed almost entirely out of hydrogen and helium, must have initiated the creation of all heavier chemical elements. Here we report…

In this paper the role of very massive pop III stars in the chemical enrichment of the early universe is discussed. We first compare our predictions with the abundance ratios measured in the high redshift Lyman-alpha forest to check whether…

Because massive, low-metallicity population III (PopIII) stars may produce very powerful long gamma-ray bursts (LGRBs), high-redshift GRB observations could probe the properties of the first stars. We analyze the correlation between early…

We present high resolution observations of an extremely metal-poor damped Lyman-alpha system, at z_abs = 2.3400972 in the spectrum of the QSO J0035-0918, exhibiting an abundance pattern consistent with model predictions for the supernova…

Damped Ly-alpha absorbers (DLAs) can be used to measure gas-phase metallicities at large cosmological lookback times with high precision. Relative abundances can still be measured accurately deep into the reionization epoch (z > 6) using…

Recent data from the James Webb Space Telescope suggest that there are realistic prospects for detecting the earliest generation of stars at redshift ~20. These metal-poor, gaseous Population III (Pop III) stars are likely in the mass range…

Extremely metal poor stars have been the focus of much recent attention owing to the expectation that their chemical abundances can shed light on the metal and dust yields of the earliest supernovae. We present our most realistic simulation…

Recent studies have highlighted that galaxies at z = 6-8 fall short of producing enough ionizing photons to reionize the IGM, and suggest that Population III stars could resolve this tension, because their harder spectra can produce ~10x…