Pointwise characteristic factors for the multiterm return times theorem

This paper is an update and extension of a result the authors first proved in 2003. The goal of this paper is to study factors which are known to be L^2-characteristic for certain nonconventional averages and prove that these factors are pointwise characteristic for the multidimensional return times averages.Comment: 31 pages Submitted and Accepted to ETDS Dan Rudolph Memorial Volume. This version is the final accepted copy and includes all of the revisions recommended by the referee

Differences in the gas and dust distribution in the transitional disk of a sun-like young star, PDS 70

This is the author accepted manuscript. The final version is available from the publisher via the DOI in this recordThe American Astronomical Society. All rights reserved. We present ALMA 0.87 mm continuum, HCO + J = 4-3 emission line, and CO J = 3-2 emission line data of the disk of material around the young, Sun-like star PDS 70. These data reveal the existence of a possible two-component transitional disk system with a radial dust gap of 0.″42 ±0.″05, an azimuthal gap in the HCO + J = 4-3 moment zero map, as well as two bridge-like features in the gas data. Interestingly these features in the gas disk have no analog in the dust disk making them of particular interest. We modeled the dust disk using the Monte Carlo radiative transfer code HOCHUNK3D using a two-disk component. We find that there is a radial gap that extends from 15 to 60 au in all grain sizes, which differs from previous work.This work is supported supported by the NASA XRP grants NNX17AF88G and NNX16AJ75G. MC thanks the support from the Centro de Astrofísica de Valparaíso. S.K. acknowledges support from an STFC Rutherford Fellowship (ST/J004030/1) and ERC Starting Grant (Grant Agreement No. 639889). This work is supported by the Astrobiology Center Program of National Institutes of Natural Sciences (NINS) (Grant Number: AB281013) and by MEXT KAKENHI No. 17K05399 (EA). Y.H. is currently supported by Jet Propulsion Laboratory, California Institute of Technology, under a contract from NASA. This paper makes use of the following ALMA data: ADS/JAO.ALMA#2015.1.00888.S. ALMA is a partnership of ESO (representing its member states), NSF (USA) and NINS (Japan), together with NRC (Canada), MOST and ASIAA (Taiwan), and KASI (Republic of Korea), in cooperation with the Republic of Chile. The Joint ALMA Observatory is operated by ESO, AUI/NRAO, and NAOJ. The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, In

Evolution chronologique des précipitations dans le Sud-Est du Zaïre. Comparaison avec celle des pays voisins

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