The large COMPASS polarized solid ammonia target for Drell-Yan measurements with a pion beam
The result's identifiers
Result code in IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68081731%3A_____%2F22%3A00556655" target="_blank" >RIV/68081731:_____/22:00556655 - isvavai.cz</a>
Alternative codes found
RIV/00216208:11320/22:10441078 RIV/00216208:11320/22:10458277
Result on the web
<a href="https://www.sciencedirect.com/science/article/pii/S0168900221009918" target="_blank" >https://www.sciencedirect.com/science/article/pii/S0168900221009918</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.1016/j.nima.2021.166069" target="_blank" >10.1016/j.nima.2021.166069</a>
Alternative languages
Result language
angličtina
Original language name
The large COMPASS polarized solid ammonia target for Drell-Yan measurements with a pion beam
Original language description
The transversely polarized target (PT) of the COMPASS (NA58) collaboration at CERN has been used for Drell-Yan measurements in 2015 and 2018. The transverse spin structure of the proton has been studied using a negative pion beam and a solid ammonia target. Employing the dynamic nuclear polarization (DNP) method, proton polarization values of more than 80% have been routinely achieved after one day, at a homogeneous magnetic field of 2.5 T and using a He-3/He-4 dilution refrigerator. During the data-taking the target operates in a transversely oriented magnetic dipole field at 0.6 T. This so-called frozen spin operation mode without the DNP pumping process leads to a slow depolarization of the target material, which is further accelerated by the heat input of the pion beam, produced secondary particles and radiation damage effects to the target material. Ammonia has the highest resistance against radiation-induced depolarization among known solid target materials. The proton polarization has been measured by the nuclear magnetic resonance (NMR). Relaxation times of about 1100 h have been observed for the proton polarization resulting in an average polarization between 68% and 76% during about two weeks long data-taking periods. To achieve a systematic uncertainty of the polarization Delta P/P as low as 3.2% and a statistical one of less than 1.8% two large target cells with appropriate positioning of the NMR-coils have been built.
Czech name
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Czech description
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Classification
Type
J<sub>imp</sub> - Article in a specialist periodical, which is included in the Web of Science database
CEP classification
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OECD FORD branch
10303 - Particles and field physics
Result continuities
Project
Result was created during the realization of more than one project. More information in the Projects tab.
Continuities
I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace
Others
Publication year
2022
Confidentiality
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Data specific for result type
Name of the periodical
Nuclear Instruments & Methods in Physics Research Section A
ISSN
0168-9002
e-ISSN
1872-9576
Volume of the periodical
1025
Issue of the periodical within the volume
11 February
Country of publishing house
NL - THE KINGDOM OF THE NETHERLANDS
Number of pages
10
Pages from-to
166069
UT code for WoS article
000777573700004
EID of the result in the Scopus database
2-s2.0-85121588847