相关论文: Rapid Evolution of Volatile CO from the Protostell…

Here we present high resolution (15-24 au) observations of CO isotopologue lines from the Molecules with ALMA on Planet-forming Scales (MAPS) ALMA Large Program. Our analysis employs $^{13}$CO and C$^{18}$O ($J$=2-1), (1-0), and C$^{17}$O…

High resolution ALMA observations of protoplanetary disks have revealed that many, if not all primordial disks consist of ring-like dust structures. The origin of these dust rings remains unclear, but a common explanation is the presence of…

We investigate the formation of the first stars at the end of the cosmic dark ages with a suite of three-dimensional, moving mesh simulations that directly resolve the collapse of the gas beyond the formation of the first protostar at the…

The statistical properties of circumstellar disks around young stars are important for constraining theoretical models for the formation and early evolution of planetary systems. In this brief review, I survey the literature related to…

Context. Characterizing the evolution of protoplanetary disks is necessary to improve our understanding of planet formation. Constraints on both dust and gas are needed to determine the dominant disk dissipation mechanisms. Aims. We aim to…

[abridged]CO rovibrational lines are efficient probes of warm molecular gas and can give unique insights into the inner 10 AU of proto-planetary disks. Recent studies have found a relation between the ratio of lines originating from the…

Young circumstellar disks that are still embedded in dense molecular envelopes may differ from their older counterparts, but are historically difficult to study because emission from a disk can be confused with envelope or outflow emission.…

The potential for planet formation of a circumstellar disk depends on the dust and gas reservoirs, which evolve as a function of the disk age. The ALMA Large Program AGE-PRO has measured several disk properties across three star-forming…

Methods. We use the recently developed disk code ProDiMo to calculate the physico-chemical structure of protoplanetary disks and apply the Monte-Carlo line radiative transfer code RATRAN to predict observable line profiles and fluxes. We…

We describe results from a survey for J=3-2 12CO emission from visible stars with an infrared excess. The line is clearly detected in 21 objects, with molecular gas (>10^-3 Jupiter masses) common in targets with infrared excesses >0.01…

ALMA observations of protoplanetary disks confirm earlier indications that there is a clear difference between the dust and gas radial extents. The origin of this difference is still debated, with both radial drift of the dust and optical…

High-resolution observations show that typically both the dust and the gas in nearby extended protoplanetary disks are structured, possibly related to radial and azimuthal variations in the disk density and/or chemistry. The aim of this…

The increased sensitivity of millimeter-wave facilities now makes possible the detection of low amounts of gas in debris disks. Some of the gas-rich debris disks harbor peculiar properties, with possible pristine gas and secondary generated…

The molecular composition inside the dust sublimation zones of protoplanetary disks is mostly unknown but important to understanding terrestrial planet formation. A few molecules have been observed from this region, specifically CO, H2O, OH…

Context. Time dependent gas-grain chemistry can help us understand the layered structure of species deposited onto the surface of grains during the lifetime of a protoplanetary disk. The history of trapping important quantities of carbon-…

Large-scale radial transport of solids appears to be a fundamental consequence of protoplanetary disk evolution based on the presence of high temperature minerals in comets and the outer regions of protoplanetary disks around other stars.…

In regions where stars form, variations in density and temperature can cause gas to freeze-out onto dust grains forming ice mantles, which influences the chemical composition of a cloud. The aim of this paper is to understand in detail the…

The evolution of a circumstellar disk from its gas-rich protoplanetary stage to its gas-poor debris stage is not understood well. It is apparent that disk clearing progresses from the inside-out on a short time scale and models of…

We re-examine the constraints provided by Herschel Space Observatory data regarding cold water emission from protoplanetary disks. Previous disk models that were used to interpret observed water emission concluded that oxygen (O/H) is…

We carried out a 12CO(3-2) survey of 52 southern stars with a wide range of IR excesses (LIR/L*) using the single dish telescopes APEX and ASTE. The main aims were (1) to characterize the evolution of molecular gas in circumstellar disks…