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 ...

he public's desire for mobile communications and computing, as evidenced by the popularity of cellular phones, pagers, and laptop computers, combined with the rapid growth in demand for Internet access, suggest a very promising future for wireless data services. The key to realizing this potential is the development and deployment of high-performance radio systems. While many proposals for thir...

We present results of a recent Chandra X-ray Observatory observation of the central compact object (CCO) in the supernova remnant Cassiopeia A. This observation was obtained in an instrumental configuration that combines a high spatial resolution with a minimum spectral distortion, and it allowed us to search for pulsations with periods longer than ≈ 0.68 s. We found no evidence of extended emi...

There are ∼ 1, 0.1 and 0.01 gravitationally lensed X-ray sources per square degree with soft X-ray fluxes exceeding 10 −15 , 10 −14 and 10 −13 ergs s −1 cm −2 respectively. These sources will be detected serendipitously with the Chandra X-ray Observatory at a rate of 1–3 lenses per year of high resolution imaging. The low detection rate is due to the small area over which the HRC and ACIS camer...

We present six Chandra X-ray spectra and light curves obtained for the nova V1494Aql (1999 #2) in outburst. The first three observations were taken with ACIS-I on days 134, 187, and 248 after outburst. The count rates were 1.00, 0.69 and 0.53 cps, respectively. We found no significant periodicity in the ACIS light curves. The X-ray spectra show continuum emission and lines originating from N an...