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1.
In this article, we will briefly review the current empirical understanding of the relation between accretion state and outflows in accreting stellar mass black holes. The focus will be on the empirical connections between X-ray states and relativistic (‘radio’) jets, although we are now also able to draw accretion disc winds into the picture in a systematic way. We will furthermore consider the latest attempts to measure/order jet power, and to compare it to other (potentially) measurable quantities, most importantly black hole spin. 相似文献
2.
Aya Bamba Hiroya Yamaguchi Katsuji Koyama Junko S. Hiraga Steve Holt John P. Hughes Hideaki Katagiri Jun Kataoka Satoru Katsuda Shunji Kitamoto Motohide Kokubun Hironori Matsumoto Emi Miyata Koji Mori Hiroshi Nakajima Masanobu Ozaki Rob Petre Akiko Sekiguchi Tadayuki Takahashi Takaaki Tanaka Yukikatsu Terada Hiroshi Tomida Yohko Tsuboi Masahiro Tsujimoto Hiroshi Tsunemi Yasunobu Uchiyama Masaru Ueno Shin Watanabe 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008,41(3):411-415
SN 1006 is one of the supernova remnants (SNRs) with relatively low-temperature electrons, considering the young age of just 1000 years. We carried out SN 1006 mapping observations with the X-ray Imaging Spectrometers (XIS) and the Hard X-ray Detector (HXD) onboard Suzaku, the fifth Japanese X-ray satellite. Thanks to the excellent spectral resolution of XIS in the soft X-ray band, H-like and He-like oxygen emission lines were clearly detected, and we could make a map of the line intensity, and as well as a flux and the photon index of nonthermal component. We found that these parameters have spatial dependences from region to region in the SNR; the north region is bright in nonthermal, while dim in thermal; the east region is bright in both nonthermal and thermal; the inner region shows dim nonthermal and bright thermal emission. The photon index is the smallest in the north region. 相似文献
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The Broad-Band X-Ray Telescope (BBXRT) has been designed to perform high sensitivity, moderate resolution spectrophototnetry of X-ray sources in the 0.3–12 keV band from the Shuttle. It consists of a coaligned pair of high throughput, conical X-ray imaging mirrors, with a cryogenically-cooled, multiple element, Si(Li) spectrometer at the focus of each. On axis, BBXRT will have an effective area of 580 cm2 at 2 keV and 250 cm2 at 7 keV, and a spectral resolution of 110 eV at 2 keV and 150 eV at 7 keV. A 104 s observation with BBXRT will allow a determination of the continuum spectral shape for sources near the Einstein deep survey limit. 相似文献
4.
We highlight the effect on space-telescope temperatures of thedirectionality of the radiative properties of materials, by showing results from a Monte-Carlo simulation of telescope cooling. The need for further measurements of directional properties is stressed. 相似文献
5.
Rob R. Landis Paul A. Abell David J. Korsmeyer Thomas D. Jones Daniel R. Adamo 《Acta Astronautica》2009,65(11-12):1689-1697
In late 2006, NASA's Constellation Program sponsored a study to examine the feasibility of sending a piloted Orion spacecraft to a near-Earth object. NEOs are asteroids or comets that have perihelion distances less than or equal to 1.3 astronomical units, and can have orbits that cross that of the Earth. Therefore, the most suitable targets for the Orion Crew Exploration Vehicle (CEV) are those NEOs in heliocentric orbits similar to Earth's (i.e. low inclination and low eccentricity). One of the significant advantages of this type of mission is that it strengthens and validates the foundational infrastructure of the United States Space Exploration Policy and is highly complementary to NASA's planned lunar sortie and outpost missions circa 2020. A human expedition to a NEO would not only underline the broad utility of the Orion CEV and Ares launch systems, but would also be the first human expedition to an interplanetary body beyond the Earth–Moon system. These deep space operations will present unique challenges not present in lunar missions for the onboard crew, spacecraft systems, and mission control team. Executing several piloted NEO missions will enable NASA to gain crucial deep space operational experience, which will be necessary prerequisites for the eventual human missions to Mars.Our NEO team will present and discuss the following:
- • new mission trajectories and concepts;
- • operational command and control considerations;
- • expected science, operational, resource utilization, and impact mitigation returns; and
- • continued exploration momentum and future Mars exploration benefits.
Keywords: NASA; Human spaceflight; NEO; Near-Earth asteroid; Orion spacecraft; Constellation program; Deep space 相似文献
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7.
Aqueous long chain alcohol solutions have a surface tension which presents a minimum as a function of the temperature. At this particular temperature, the dimensionless Marangoni number is vanishing. It is thus expected that around the temperature of the minimum, Marangoni Convection would be slowered with a convective pattern deeply modified. An experiment to be performed in microgravity during the Texus 8 flight is described. 相似文献
8.
Rob Schmitz 《西南航空》2001,60(4):82-83
Changning County, Sichuan Province- The ants are on my trail. Thinking I've lost them, I stop to rest. But a few of them have battled their way up the steep path and are catching up to me. Soon I'll be done for. In desperation, I go off trail,weaving through grass so high it blocks out the sun. 相似文献
9.
M. Miceli A. Decourchelle J. Ballet F. Bocchino J. Hughes U. Hwang R. Petre 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008,41(3):390-395
In the framework of the study of supernova remnants and their complex interaction with the interstellar medium and the circumstellar material, we focus on the galactic supernova remnant W49B. Its morphology exhibits an X-ray bright elongated nebula, terminated on its eastern end by a sharp perpendicular structure aligned with the radio shell. The X-ray spectrum of W49B is characterized by strong K emission lines from Si, S, Ar, Ca, and Fe. There is a variation of the temperature in the remnant with the highest temperature found in the eastern side and the lowest one in the western side. The analysis of the recent observations of W49B indicates that the remnant may be the result of an asymmetric bipolar explosion where the ejecta are collimated along a jet-like structure and the eastern jet is hotter and more Fe-rich than the western one. Another possible scenario associates the X-ray emission with a spherical explosion where parts of the ejecta are interacting with a dense belt of ambient material. To overcome this ambiguity we present new results of the analysis of an XMM-Newton observation and we perform estimates of the mass and energy of the remnant. We conclude that the scenario of an anisotropic jet-like explosion explains quite naturally our observation results, but the association of W49B with a hypernova and a γ-ray burst, although still possible, is not directly supported by any evidence. 相似文献
10.
Edwards Christopher S. Christensen Philip R. Mehall Greg L. Anwar Saadat Tunaiji Eman Al Badri Khalid Bowles Heather Chase Stillman Farkas Zoltan Fisher Tara Janiczek John Kubik Ian Harris-Laurila Kelly Holmes Andrew Lazbin Igor Madril Edgar McAdam Mark Miner Mark O’Donnell William Ortiz Carlos Pelham Daniel Patel Mehul Powell Kathryn Shamordola Ken Tourville Tom Smith Michael D. Smith Nathan Woodward Rob Weintraub Aaron Reed Heather Pilinski Emily B. 《Space Science Reviews》2021,217(7):1-37
Space Science Reviews - Modern observatories have revealed the ubiquitous presence of magnetohydrodynamic waves in the solar corona. The propagating waves (in contrast to the standing waves) are... 相似文献