We present the distance priors from the finally released P lanck TT,TE,EE + lowE data in 2018. The uncertainties are around 40% smaller than those from P lanck 2015 TT+lowP. In order to check the validity of these new distance priors, we adopt the distance priors to constrain the cosmological parameters in different dark energy models, including the ΛCDM model, the wCDM model and the CPL model, and conclude that the distance priors provide consistent constraints on the relevant cosmological parameters compared to those from the full P lanck 2018 data release.
How mass is accumulated from cloud-scale down to individual stars is a key open question in understanding highmass star formation. Here, we present the mass accumulation process in a hub-filament cloud G22 that is composed of four supercritical filaments. Velocity gradients detected along three filaments indicate that they are collapsing with a total mass infall rate of about 440 M e Myr −1 , suggesting the hub mass would be doubled in six free-fall times, adding up to ∼2 Myr. A fraction of the masses in the central clumps C1 and C2 can be accounted for through large-scale filamentary collapse. Ubiquitous blue profiles in HCO + (3-2) and 13 CO(3-2) spectra suggest a clump-scale collapse scenario in the most massive and densest clump C1. The estimated infall velocity and mass infall rate are 0.31 km s −1 and 7.2×10 −4 M e yr −1 , respectively. In clump C1, a hot molecular core (SMA1) is revealed by the Submillimeter Array observations and an outflow-driving high-mass protostar is located at the center of SMA1. The mass of the protostar is estimated to be 11-15 M e and it is still growing with an accretion rate of 7×10 −5 M e yr −1 . The coexistent infall in filaments, clump C1, and the central hot core in G22 suggests that pre-assembled mass reservoirs (i.e., high-mass starless cores) may not be required to form high-mass stars. In the course of high-mass star formation, the central protostar, the core, and the clump can simultaneously grow in mass via core-fed/disk accretion, clump-fed accretion, and filamentary/cloud collapse.
We use Planck data released in 2015 to constrain the abundance of primordial black holes (PBHs) in dark matter in two different reionization models (one is the instantaneous reionization and the other is the asymmetric reionization), and significantly improve the existing upper limits on the abundance of PBHs by around two orders of magnitude. These new limits imply that the event rates of mergers of PBH binaries (Gpc −3 yr −1 ) are less than 0.002 for M pbh = 30M , 5 for M pbh = 10M and 2000 for M pbh = 2M at 95% confidence level (C.L.), and thus the gravitational-wave event GW150914 is very unlikely produced by the merger of a PBH binary.
We try to reconcile the tension between the local 2.4 % determination of Hubble constant and its global determination by Planck CMB data and BAO data through modeling the dark energy variously. We find that the chi-
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