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Background shielding

Fignre 135 Environmentar background count, Bg > Bs> 464 keV for a variety of detectors in a low background shield as a function of detector efficiency (adapted from data in Keyser etal. (1990)... [Pg.255]

A prospective purchaser might consider it worthwhile to obtain evidence of the measured background of the specific detector before buying. It may not be possible to reproduce the performance of the manufacturer s low-background shield in which the test was done, but such data win give a benchmark against which the measurements after installation can be evaluated. [Pg.265]

Canberra. Ultra Low-Background Shield - Model 777 http //www.canberra.com/pdf/Products/Detectors pdf/ 2m777.pdf... [Pg.278]

When equation 12 is vaUd, the detector is said to be a background-limited infrared photodetector (BLIP). When this is the case, attempts often are made to improve D by cold shielding which reduces ( ). The ideal D is shown in Figure 3 as a function of wavelength with background photon flux as a parameter. The line of termination in the lower left corner represents TN values for a 180° (27T) detector field of view, 300 K ambient background... [Pg.422]

The detector itself may be shielded from background y-rays by means of an annular shield of W or Pb, and absorbers in the form of appropriate metal foils are placed between the detector and the specimen. These reduce the intensity of the continuum of Bremsstrahlung radiation and also prevent back-scattered protons from entering the detector which would degrade the observed spectrum. [Pg.101]

The refrigerator itself is shielded with a 20 cm thick low activity lead and a 10 cm thick borated PET. Nitrogen is fluxed between the external lead shield and the cryostat to avoid any Rn contribution to the detector background. Measurements of residual radioactivity have been carried out on several Pb samples [103], For the roman lead, a contamination lower than 4 mBq/Kg (in 210Pb) is to be compared with 250 mBq/Kg of a modem lead (Johnson Mattey). [Pg.367]

In the following we will consider the case of matter fields (non-relativistic fermions) located in the space between voids or cavities, such that the matter fields will build up a quantum pressure on the voids. Even if we assume that the matter fields are non-interacting, an effective interaction between the empty regions of space will still arise in the background of the fermionic matter fields, since the cavities - depending on their geometric arrangement - can shield the free movement of the matter modes. [Pg.235]

The 2 emission at 394 nm and the HPO emission at 526 nm are selected by means of appropriate narrow bandpass filters and the lower half of the flame is shielded to reduce background... [Pg.105]

The regional-based survey pattern of the GSC-determined Hg concentrations (ppb) in stream sediments across Canada is shown in Fig.1. Of particular interest are (i) the high Hg concentration cluster near the central north-eastern border of the Yukon Territory (Survey Zone 3), (ii) the somewhat elevated background levels in the southern portions of the Canadian Shield along the Great Lakes, (iii) the scattered pattern of similar values throughout British Columbia, Labrador and... [Pg.256]

March 2 A bill to shield gun manufacturers and dealers from lawsuits is overwhelmingly defeated in the Senate. The Republicans had withdrawn their support for the bill after Democrats had succeeded in adding amendments that would renew the ban on assault weapons, require child safety locks on all handguns, and require background checks on gun purchases at gun shows. [Pg.111]

Divide into two portions one should have white background and the other black. The illumination should be from a shielded 100-W bulb daylight-quality light source, which provides an intensity of illumination of not less than 100 and not more than 350 fc, at a point 25.4 cm (10 in.) from its source. [Pg.726]


See other pages where Background shielding is mentioned: [Pg.186]    [Pg.186]    [Pg.193]    [Pg.194]    [Pg.255]    [Pg.265]    [Pg.266]    [Pg.266]    [Pg.186]    [Pg.186]    [Pg.193]    [Pg.194]    [Pg.255]    [Pg.265]    [Pg.266]    [Pg.266]    [Pg.297]    [Pg.1419]    [Pg.448]    [Pg.174]    [Pg.380]    [Pg.383]    [Pg.1602]    [Pg.58]    [Pg.31]    [Pg.35]    [Pg.203]    [Pg.81]    [Pg.71]    [Pg.252]    [Pg.347]    [Pg.348]    [Pg.348]    [Pg.368]    [Pg.205]    [Pg.324]    [Pg.465]    [Pg.106]    [Pg.217]    [Pg.212]    [Pg.9]    [Pg.66]    [Pg.69]    [Pg.248]    [Pg.141]    [Pg.32]    [Pg.397]    [Pg.122]   
See also in sourсe #XX -- [ Pg.186 , Pg.194 , Pg.195 ]




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