Narrow Results

LCGT is the large scale cryogenic gravitational wave telescope project in Japan in order to firstly detect gravitational waves. After the detection, the detector will be served as an astronomical tool to observe the Universe in collaborative observation with Advanced LIGO, GEO HF, Advanced Virgo and AIGO detectors. LCGT will contribute both the enterprise of detecting the gravitational wave events and the worldwide network for gravitational wave astronomy. This paper summarizes the status of LCGT.

In order to determine the cross sections of astrophysical reactions at relevant energies the new Felsenkeller underground laboratory, Germany, houses a 5 MV Pelletron accelerator. The accelerator provides stable and high-intensity ion beams which are much-needed in low-background environments. The properties of the two ion sources used in the new accelerator facility are discussed: The external 134 MC-SNICS cesium sputter source providing carbon beams in tandem mode and the internal radio frequency source for hydrogen and helium beams in single-ended mode.

One important component of the ambient background in underground laboratories are neutrons, which cover a wide energy range from thermal up to 100 MeV. After a few meters rock overburden, cosmic-ray neutrons are a negligible contribution underground and the remaining flux is due to neutron production by cosmic-ray muons and by (α,n) reactions from natural radioactivity in the rock.

There are only a few measurements of the full spectral neutron flux available in the literature, a fact which hampers comparisons between laboratories and negatively affects the planning of future experiments.

In an effort to overcome this issue a setup consisting of six moderated and one unmoderated ³He neutron counters that has been used at a depth of 850 m in the Canfranc underground laboratory, Spain [1], was utilized to study the neutron flux in the 48 m deep Dresden Felsenkeller underground laboratory, Germany. At Felsenkeller, an additional counter with a lead liner was used in order to address also the high-energy flux up to several hundreds of MeV.

KAGRA is an interferometric gravitational-wave detector with 3-km arms constructed at Kamioka, Gifu, Japan. One of the key features of KAGRA is the cryogenic mirrors for the 3 km arm cavities. KAGRA plans to begin the operation before the end of 2019. KAGRA plans to join the network observation of global gravitational wave interferometers.

KAGRA is a new gravitational wave detector which aims to begin joint observation with Advanced LIGO and Advanced Virgo from late 2019. Here, we present KAGRA’s possible upgrade plans to improve the sensitivity in the decade ahead. Unlike other state-of-the-art detectors, KAGRA requires different investigations for the upgrade since it is the only detector which employs cryogenic cooling of the test mass mirrors. In this paper, investigations on the upgrade plans which can be realized by changing the input laser power, increasing the mirror mass, and injecting frequency dependent squeezed vacuum are presented. We show how each upgrade affects to the detector frequency bands and also discuss impacts on gravitational-wave science. We then propose an effective progression of upgrades based on technical feasibility and scientific scenarios.

Aimed at reducing gangue pollution, an underground gangue separation method was put forward in this paper. The impact crushing experiment was performed on coal and gangue from three mines in China. There were five impact velocity levels in the experiment. The experimental results indicate that the 50 mm material ratio for coal is larger than that for gangue at the same impact velocity, which proves that the separation method is feasible. For different mines, the crushed granularities of coal and gangue are different at the same impact velocity. The sieving boundary depends on the mechanical and physical properties of gangue and coal. By using the separation equipment underground, the discharge amount of gangue in Liangzhuang Mine could be decreased by 163100 tonnes per year, with an annual benefit of 52464900 yuan.

LCGT shall be planned to be the large scale cryogenic gravitational wave telescope in order to firstly detect gravitational waves. After the detection, the detector will be served as an astronomical tool to observe the Universe. In collaborative observation by Advanced LIGO, GEO HF and Advanced Virgo projects, LCGT is desired with AIGO to contribute both the enterprise of detecting the gravitational wave events and the worldwide network for gravitational wave astronomy. This paper summarizes the status of LCGT.

Mix the related studies on underground mine rescue team equipment at home and abroad; analysis the various elements of transport equipment limitations and requirements of the man-machine-environment system after the mine accident. Against the problem for the mine rescue teams in the mine rescue process. Determine the mine rescue team equipment underground transport system conceptual design to produce a transport equipment to improve the efficiency of underground mine rescue.

Papers from the design orientation, functional design, human-computer interaction, technical principles, product placement and product modelling, six aspects of high-speed type exoskeleton carrying line man-machine system, are described in detail in the key design.