Electron conditioning of technical surfaces at cryogenic and room temperature in the 0-1 keV energy range

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68407700%3A21220%2F23%3A00370755" target="_blank" >RIV/68407700:21220/23:00370755 - isvavai.cz</a>

Result on the web

<a href="https://doi.org/10.1016/j.vacuum.2022.111656" target="_blank" >https://doi.org/10.1016/j.vacuum.2022.111656</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.vacuum.2022.111656" target="_blank" >10.1016/j.vacuum.2022.111656</a>

Result language

angličtina

Original language name

Electron conditioning of technical surfaces at cryogenic and room temperature in the 0-1 keV energy range

Original language description

In the superconducting magnets of the Large Hadron Collider (LHC) at CERN, most of the beam-induced heat load is intercepted by a beam-screen (BS) cryogenically cooled to 5-20 K. When circulating the bunched proton beam, an electron cloud (EC) can form and bombard the BS copper surface with high doses of predominantly low-energy electrons, which desorb gas and consequently increase the pressure. The beam-induced pressure rise decreases during operation as the electron irradiation diminishes the secondary electron yield (SEY) and the electron-stimulated desorption (ESD) yield, a phenomenon referred to as 'beam conditioning'. Low ESD and SEY values achieved rapidly are requisite to mitigate EC and maintain UHV in storage rings. We report data on ESD and SEY electron conditioning completed at cryogenic temperature with 0-1 keV electrons up to an electron dose of 5.10-3 C mm-2. Our results show that SEY conditioning depends on the primary electron energy and also that ESD yield significantly decreases with temperature. At 15 K, the amorphous-carbon coating and laser-treated copper present SEY below 1.1 and have initial ESD yields 3-6 times lower than OFE copper. Our results conform to the SEY and ESD's general understanding and extend it towards cryogenic temperatures.

Czech name

—

Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

—

OECD FORD branch

10302 - Condensed matter physics (including formerly solid state physics, supercond.)

Project

—

Continuities

S - Specificky vyzkum na vysokych skolach

Publication year

2023

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Vacuum

ISSN

0042-207X

e-ISSN

1879-2715

Volume of the periodical

207

Issue of the periodical within the volume

january

Country of publishing house

GB - UNITED KINGDOM

Number of pages

8

Pages from-to

1-8

UT code for WoS article

000885990100001

EID of the result in the Scopus database

2-s2.0-85141497826