We present new observations on PKS 2155-304 with the Chandra Low Energy Transmission Grating Spectrometer (LETG), using the Advanced CCD Imaging Spectrometer (ACIS). We confirm the detection of an absorption line plausibly identified as O VIII Lyα from the warm-hot intergalactic medium associated with a small group of galaxies along the line of sight, as originally reported by Fang et al. 2002 ...

Context. The outer Galaxy, where the environmental conditions are different from the solar neighborhood, is a laboratory in which it is possible to investigate the dependence of star formation process on the environmental parameters. Aims. We investigate the X-ray properties of NGC 1893, a young cluster (∼1–2 Myr) in the outer part of the Galaxy (galactic radius ≥11 kpc) where we expect differe...

هدف: این پژوهش با هدف بررسی اثر آموزش برنامه هوش موفق استرنبرگ بر افزایش خلاقیت و تحمل ابهام دانش‌­آموزان انجام شد. روش: روش ­آزمایشی طرح پیش ­آزمون پس پیگیری گروه کنترل بود. جامعۀ آماری را 15842 نفر ازدانش‌­آموزان پسر کلاس چهارم در سال تحصیلی1399-1400 شهر اصفهان تشکیل دادند که30 نمونه‌­گیری تصادفی چند مرحله­‌ای انتخاب به صورت دو آزمایش (15 نفر) گمارده شدند. ده جلسه برنامه‌­ی دریافت نمود. داده­...

The satellite-based cloud condensation nuclei (CCN) proxies used to quantify the aerosol-cloud interactions (ACIs) are column integrated and do not guarantee vertical co-location of aerosols clouds. This has encouraged use height-resolved measurements spaceborne lidars for ACI studies led advancements in lidar-based CCN retrieval algorithms. In this study, we present a comparison between number...

We study the connection between X-ray and UV properties of broad absorption line (BAL) wind in highly variable quasar PG 2112+059 by comparing Chandra-ACIS data with contemporaneous HST/STIS spectra three different epochs. observe a correlation whereby an increase equivalent-widths (EWs) BALs is accompanied redder spectrum. The growth EWs also significant dimming soft emission (<2 keV), consist...

We present a Chandra ACIS observations of N157B, a young supernova remnant (SNR) located in the 30 Doradus star-formation region of the Large Magellanic Cloud. This remnant contains the most energetic pulsar known (J053747.39–691020.2; Ė = 4.8 × 10 ergs s), which is surrounded by a X-ray bright nonthermal nebula that likely represents a toroidal pulsar wind terminal shock observed edge-on. Two ...