We have implemented a Monte Carlo algorithm to model and predict the response of various kinds of CCDs to X-ray photons and minimally-ionizing particles and have applied this model to the CCDs in the Chandra X-ray Observatory's Advanced CCD Imaging Spectrometer. This algorithm draws on empirical results and predicts the response of all basic types of X-ray CCD devices. It relies on new solution...

PSR 0628-28 is an X-ray emitting radio pulsar which was observed with Advanced CCD Imaging Spectrometer (ACIS) on board Chandra on 2001 November 04 and on 2002 March 25 for 2700 s and 17000 s, respectively. The source countrate was 0.0111±0.0008cps. We detected pulsations consistent with the radio frequency of f = 0.80370338 ± 0.000059 at a pulsed fraction 25.4%±%2 making PSR 062828 to be the l...

The red quasar 3C212 (z = 1.049) is one of the most distant and most luminous AGN which has shown evidence of an X-ray warm absorber. In order to further investigate this unusual quasar, we used Chandra/ACIS-S to observe 3C212 for 19.5 ksec, resulting in a net detection of ∼ 4000 counts. The Chandra data confirm the presence of an excess absorbing column NH ≈ 4 × 10 21 cm at the quasar redshift...

We present the results of the first X-ray gratings spectroscopy observations of a planetary nebula (PN), the X-ray-bright, young BD+303639. We observed BD+303639 for a total of 300 ks with the Chandra X-ray Observatory’s Low Energy Transmission Gratings in combination with its Advanced CCD Imaging Spectrometer (LETG/ACIS-S). The LETG/ACIS-S spectrum of BD+303639 is dominated by H-like resonance...

We report the discovery of X-ray emission from NGC 7027, a prototypical object for the study of the formation and evolution of planetary nebulae (PNs). Observations with the Advanced CCD Imaging Spectrometer (ACIS) aboard the Chandra X-ray Observatory show that the X-ray emission from NGC 7027 is extended and is bipolar in morphology. The ACIS spectrum displays strong emission from highly ioniz...

We report the detection of well resolved, extended X-ray emission from the young planetary nebula BD +30 3639 using the Advanced CCD Imaging Spectrometer (ACIS) aboard the Chandra X-ray Observatory. The X-ray emission from BD +30 3639 appears to lie within, but is concentrated to one side of, the interior of the shell of ionized gas seen in high-resolution optical and IR images. The relatively ...

Context. It is still debated whether star formation process depends on environment. In particular it is yet unclear whether star formation in the outer Galaxy, where the environmental conditions are, theoretically, less conducive, occurs in the same way as in the inner Galaxy. Aims. We investigate the population of NGC 1893, a young cluster (∼3−4 Myr) in the outer part of the Galaxy (RG ≥ 11 kp...

A bstract The optical characieristics (irünsniission and rellection. absorpiion and scatiering coeilicienis) of the Si iianowires ohtaiiied by electrocheiiiical rrratnieiii of Si wakrs were studied experimenrally in spectral range 350 750 nrn. usiiig the differeni arigles ol'incidencr aiid iiiasuring h e aiiyiilar diwihution of the rellected (scattered) lighi. Theoreiical treatineni niade on th...