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1.
More and more proposals, or potential projects have been proposed in recent two years. We try to briefly outline these new proposals, although most of them are in fact only in their conception studies. The progress of previously mentioned projects, like Space Solar Telescope (SST), the Hard X-ray Modulation Telescope (HXMT), as well as newly initiated LUnar Resource Explorer (LUREX), will be introduced elsewhere. 相似文献
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Gaurang B. Yodh 《Space Science Reviews》1996,75(1-2):199-212
This paper discusses the properties of using the water Cherenkov technique to detect air showers in the few hundred GeV to 100 TeV energy range. The responses of a 6 m2 2 m deep water Cherenkov counter and that of a 6 m2 10cm thick scintillator-lead sandwich counter to air shower electrons and photons is described. The advantages of water Cherenkov detector is outlined. Its application to do VHE gamma ray astronomy is discussed with particular reference to the MILAGRO telescope currently under construction. Milagro, a water-Cherenkov detector to do gamma ray astronomy above 100 Gev, uses an existing pool 60m × 80m by 8m, located in the Jemez mountains near Los Alamos, NM. The threshold of the MILAGRO detector is comparable to atmospheric Cherenkov detectors, however it has several advantages over these optical detectors. MILAGRO can operate 24 hours a day in all weather conditions and it has an open aperture which allows it to view the entire northern sky every day. These capabilities allow for a systematic all-sky survey to be done for the first time at these energies. MILAGRO will measure the Crab spectrum with high significance over a wide energy range, it will detect and measure the spectra from AGN's such as MRK 421 and it will search for short duration bursts from GRBs and possibly evaporating PBHs. 相似文献
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Wei Wang Yihua YanMaohai Huang 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008
Very low frequency interferometry among two astronomical experiments has been proposed and accepted for further study for the second phase of China’s lunar exploration programme (the Chang’E Programme), which is envisaged to operate a lander and a rover on the surface of the moon. This experiment is an interferometer experiment in the very low frequency (VLF, f < 15 MHz) regime of radio frequencies with at least degree-level angular resolution. The goals include observing solar storm activities, Coronal Mass Ejections, Auroral Kilometric Radiation, and planetary radiation in the solar system, studying the origin of Cosmic Rays, spectral properties of pulsars, surveying ionized hydrogen in the Galaxy, and exploring coherent radio emissions. 相似文献
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S.G. Anokhin 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008
We present here new XMM-Newton observations of 3 relatively cool clusters at z ≈ 0.4, complemented by archival observations of 3 other clusters at similar redshift. We derived the M–T and R–T relations from the hydrostatic equation using an isothermal temperature distribution. 相似文献
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Michael F. Bietenholz Norbert Bartel 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008,41(3):424-428
The unusual core-collapse supernova 1986J, in the nearby spiral NGC 891, is the first modern supernova in which evidence of a compact remnant of the supernova has been seen. This evidence comes from recent VLBI images, which show the emergence of a new radio component in the center of the expanding radio shell. The new component shows an inverted radio spectrum contrasting with that of the shell. The new component is likely radio emission associated with the black-hole or neutron star compact remnant of the explosion, which would mark the first direct observational link between a modern supernova and such a compact remnant. We report here on our recent VLBI images at 22 and 5 GHz, as well as on our monitoring of the integrated radio spectrum of SN 1986J. In the 22 GHz image, the central component is marginally resolved. 相似文献
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P.E.J. Nulsen 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1984,3(10-12)
Rapidly cooling gas is commonly found near the centres of clusters of galaxies. The structure of the resulting gas flows is reviewed. Total gas cooling rates of several hundred M yr−1 have been observed in a number of cases. Thermal instability and the ultimate fate of the cooled gas are discussed. The cooled gas could easily have formed a massive central galaxy. 相似文献
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《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2020,65(2):745-755
The possible association with the high-energy neutrino event IceCube-170922A has sparked interest in the blazar TXS 0506+056. We present 72 instantaneous 1–22 GHz spectra measured over the past 20 years with the RATAN-600 telescope and compare them with the results of observations of 700 variable Active Galactic Nuclei (AGN) studied within the same program. The recent radio flare of TXS 0506+056 started from a minimum in 2013 and reached its first peak in December 2017 and a second peak in May-June 2018. This was the third strong radio flare in this source since 1997. The spectrum remains nearly flat during the flares. The spectral shape and variability pattern observed in TXS 0506+056 are typical for variable AGN. RadioAstron Space VLBI observations in 2013–2015 did not detect TXS 0506+056 on space-ground baselines of more than 9 Earth diameters. However, an observation on 23 September 2015 resulted in the detection of interferometric signal on 6 Earth diameter baselines at 18 cm close to the detection limit. We consider the possibility that TXS 0506+056 and other AGN may accelerate relativistic protons more efficiently than electrons. Relativistic protons are necessary to produce both the high-energy neutrinos observed in the IceCube Observatory and the high AGN brightness temperatures implied by the RadioAstron detection. They may also provide the main contribution to the observed synchrotron radiation of parsec-scale AGN jets. This supports the suggestion that relativistic protons may play a much more important part in extragalactic astrophysics than earlier anticipated. 相似文献
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Gan Weiqun 《空间科学学报》2014,34(5)
The main activities of Chinese space solar physics in 2012–2014 include: to continue studying the mid and long-term(2016–2030) plan of Chinese space solar physics; to arrange a group of pre-study projects of space solar physics; to initiate and continue a few solar mission-level projects.This paper summarizes all these activities briefly. 相似文献