Ultimate pressures of the large electron positron collider (LEP) vacuum system

Benvenuti, C.; Bojon, J P; Chiggiato, Paolo; Losch, G

doi:10.1016/0042-207x(93)90083-m

Cited by 10 publications

(4 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The result indicates that, with all pumps in operation, the total pressure approached the expected H 2 pressure [27]. The IHG measurements were found to agree closely with those of the ISR type BAGs, showing the good performance of these gauges in the 10 -13 Torr range [27].…”

Section: The Lep Dipole Chamberssupporting

confidence: 67%

Extreme high vacuum technology for particle accelerators

Benvenuti

PACS2001. Proceedings of the 2001 Particle Accelerator Conference (Cat. No.01CH37268)

View full text Add to dashboard Cite

Linearly distributed pumping is highly desirable for Storage Rings to limit the pressure rise due to the outgassing induced by the circulating beams. As a byproduct, linear pumping allows extremely low pressures (down to the 10 -14 Torr range) to be achieved in static vacuum conditions. Non Evaporable Getters (NEGs), in the form either of a strip as adopted for LEP or of a thin film coating, may provide linear pumping in a simple and economic way. Compared to the strip, thin film coatings present the additional benefits of reduced beam-induced and thermal outgassing, larger pumping surface, lower activation temperature and applicability to vacuum chambers of very small aperture. The most recent developments of this technique and the present XHV measuring capabilities will be described and discussed with the help of some examples.

show abstract

Section: The Lep Dipole Chamberssupporting

confidence: 67%

Extreme high vacuum technology for particle accelerators

Benvenuti

PACS2001. Proceedings of the 2001 Particle Accelerator Conference (Cat. No.01CH37268)

View full text Add to dashboard Cite

show abstract

“…14 This system has the advantage of providing ESD and pumping speed measurements relative to the same sample conditions. This sequence is repeated at intervals of 40 or 50°C up to a maximum temperature of 400°C.…”

Section: Characterizationmentioning

confidence: 99%

Nonevaporable getter films for ultrahigh vacuum applications

Benvenuti

Chiggiato

Cicoira

et al. 1998

Journal of Vacuum Science &Amp; Technology A: Vacuum, Surfaces, and Films

View full text Add to dashboard Cite

Articles you may be interested inElectron-stimulated desorption from polished and vacuum fired 316LN stainless steel coated with Ti-Zr-Hf-V Electron stimulated desorption from bare and nonevaporable getter coated stainless steels Influence of electron irradiation and heating on secondary electron yields from non-evaporable getter films observed with in situ x-ray photoelectron spectroscopy Influence of the elemental composition and crystal structure on the vacuum properties of Ti-Zr-V nonevaporable getter filmsThe vacuum behavior of stainless steel vacuum chambers, ex situ sputter coated with a thin film (ϳ1 m) of getter material, has been studied to determine if after air exposure the getter film could be activated by a bakeout so as to transform the coated vacuum chamber into a pump. The materials studied so far are Ti, Zr, Hf, and some of their binary alloys. They all display an activation temperature lower than 400°C, i.e., within the reach of the baking temperature of stainless steel vacuum chambers. The lowest activation temperature of 200-250°C, measured for an equiatomic alloy of Ti and Zr, allows extension of this method to chambers made of copper and aluminum alloys. The experimental results, described here in detail, indicate that the values of the activation temperature obtained using electron stimulated desorption, pumping speed, and Auger spectroscopy measurements are self-consistent.

show abstract

“…An ultimate pressure of about 2×10 −12 Torr was achieved inside 12 m long chambers made of Al alloy and pumped by a linear non-evaporable getter (NEG) strip and a sputter-ion pump of about 50 l s −1 nominal speed [39]. This pressure could be further reduced to about 5 × 10 −13 Torr by increasing the pumping speed for Ar and CH4, not pumped by getters, with the addition of five more sputter-ion pumps of the same size [40]. Pressures in the low 10 −14 Torr range have been reproducibly achieved in a 3m long vacuum chamber [41].…”

Section: Forecasts and Constraintsmentioning

confidence: 99%

Cavity optomechanical spectroscopy constraints chameleon dark energy scenarios

Liu

Zhu

2018

Eur. Phys. J. C

View full text Add to dashboard Cite

The chameleon scalar field is a matter-coupled dark energy candidate with the screening mechanisms. In the present paper,we propose a quantum cavity optomechanical scheme to detect the possible signature of chameleons via the optical pump-probe spectroscopy. Compare to the previous experiment the sensitivity can be improved by the using of electrostatic shield and a pump-probe scheme to read the weak frequency splitting. We expect that this work will be a useful addition to the current literature on proposals to detect effects of dark energy.

show abstract

Ultimate pressures of the large electron positron collider (LEP) vacuum system

Cited by 10 publications

References 6 publications

Extreme high vacuum technology for particle accelerators

Extreme high vacuum technology for particle accelerators

Nonevaporable getter films for ultrahigh vacuum applications

Cavity optomechanical spectroscopy constraints chameleon dark energy scenarios

Contact Info

Product

Resources

About