ASCA


Also found in: Medical, Acronyms, Wikipedia.

ASCA

Fourth in the series of small (500 kg) Japanese space science satellites devoted to X-ray astronomy. It was launched into a 560-km, 31° inclination orbit in Feb. 1993, carrying a payload of four identical grazing incidence X-ray telescopes (conical foil). Two telescopes had gas scintillation proportional counters in the focal plane and two had X-ray-sensitive CCDs (provided by NASA). The mission's main strength was X-ray spectroscopy. Both types of detector gave much improved energy resolutions over ASCA's working range of 0.5–10 keV, compared with the widely used imaging proportional counter. Apart from a gradual deterioration in the energy resolution of the CCDs caused by in-orbit radiation damage, all instruments aboard ASCA continued to function up to the middle of 2000, by which time nearly 4000 separate observations had been carried out. Among many scientific advances were the detection of a population of partly obscured active galactic nuclei (see active galaxy), whose hard X-ray spectra suggested that they formed a major component of the X-ray background radiation; the first evidence for strong gravity in the form of a broad iron fluorescence line; and the measurement of metal-rich spectra in the ejecta of several supernova remnants. The mission ended in July 2000 when a geomagnetic storm caused by an unusually large solar flare irrevocably altered the orbital attitude of the satellite and the orientation of its solar panels, taking the panels away from the Sun and effectively destroying ASCA's power supply. ASCA re-entered the Earth's atmosphere in 2001. See also Astro-E2; Ginga.
References in classic literature ?
They have a few names of saints, the same with those in the Roman martyrology, but they often insert others, as Zama la Cota, the Life of Truth; Ongulari, the Evangelist; Asca Georgi, the Mouth of Saint George.
Asca, who's been with Ailey for 30 years (first as a student, and then as a company member), is mindful of how short the summer is, and how much technique he can realistically expect to impart.
The diagnostic values of anti-GP2 and ASCA antibodies in CD were evaluated using a receiver operating characteristic (ROC) curve analysis.
In line with this, SMi has announced that Colonel Thomas Williams, USAREUR G3 Fires, US Army Europe, will be presenting an overview of the ASCA Program and its role in enabling digital fires at the Network Centric Warfare 2018 conference in Rome.
The purpose of this article is to present an approach known as transformative leadership (TL) and to demonstrate how it supports and extends the ASCA National Model in ways that explicitly focus on equity, inclusion, and social justice.
Then, ASCA model was used to (1) analyze the effects of A[[beta].sub.25-35] injection, time, and their interaction on metabolic changes in hippocampus and serum of rats and (2) identify metabolites related to these effects.
ASCA (2004) career development competencies focus on awareness, readiness, the acquisition of information, goals, and the development of the knowledge and skills to achieve said goals.
In January, ASCA partnered with Dumaguete business and civic leaders to launch an InstaScram Mobile Appcontest to encourage, support and increase the number of app developers in Dumaguete.
Dye sought to determine the emphasis placed on school counseling activities by school counselors as described by the American School Counselor Association (ASCA).
However their regulation by vitamin C (VitC, ascorbic acid, AscA) has yet to be examined.
Talal Abu-Ghazaleh, Chairman of the Arab Society of Certified Accountants (ASCA) inaugurated a training session on the International Financial Reporting Standards for Small and Medium-Sized Enterprises (IFRS SMEs) in Abu Dhabi.