Measurement of qTq_T-weighted TSAs in 2015 COMPASS Drell-Yan data

In the polarised Drell-Yan experiment at the COMPASS facility at CERN the beam of negatively-charged pions with 190 GeV/c momentum and intensity about $10^8$ pions/s interacted with transversely polarised NH$_3$ target. Muon pairs produced in Drell-Yan process (DY) were detected. Recently, the first ever Transverse Spin Asymmetries (TSAs) measurement in DY has been presented by COMPASS. A complementary analysis of the TSAs weighted by powers of the dimuon transverse momentum $q_T$ are presented. In the Transverse Momentum Dependent (TMD) PDF formalism, the $q_T$-weighted TSAs can be written in terms of products of the TMD PDFs of two colliding hadrons, unlike the conventional TSAs, which are their convolutions over quarks transverse momenta. The results are compared in a straightforward way with the weighted Sivers asymmetry in the SIDIS process, released by COMPASS in 2016.Comment: 4 pages, 7 figures. In Proceedings of the 17th Workshop on High Energy Spin Physics (DSPIN-17), Dubna, Russia, September 11-15, 201

Weighted transverse spin asymmetries in 2015 COMPASS Drell-Yan data

Muon pairs created in the Drell-Yan process of a negative pion beam of 190 GeV/c momentum impinging on a transversely polarised NH$_3$ target were detected with the COMPASS spectrometer at CERN in 2015. In addition to the extraction of the transverse spin asymmetries (TSAs) from these data, a complementary analysis of the TSAs weighted by powers of the dimuon momentum $q_T$ has been performed and is presented in this paper. In the transverse momentum dependent parton distribution functions (TMD PDFs) formalism, the $q_T$-weighted TSAs can be interpreted in terms of products of the TMD PDFs of the beam pion and of the transversely polarised target proton, unlike the conventional TSAs, which are interpreted as their convolutions. This allowed us to make a straightforward comparison with the expectation based on the weighted Sivers asymmetry measured in the SIDIS process. In a similar way, the Boer-Mulders function of the pion and proton can be obtained as well.Comment: Presented on behalf of the COMPASS Collaboration at 23rd International Spin Physics Symposium - SPIN2018 - 10-14 September, 2018, Ferrara, Italy. To be published in the Proceedings of Scienc

Nucleon spin structure studies in Drell\u2013Yan process at COMPASS

The nucleon structure is presently described by Transverse Momentum Dependent (TMD) Parton Distribution Functions (PDFs), which generalise the collinear PDFs, adding partonic spin and transverse momentum degrees of freedom. The recent HERMES and COMPASS data on hadron production in deep inelastic scattering (SIDIS) of leptons off transversely polarised nucleons have provided a decisive validation of this framework. Nevertheless, the TMD PDFs should be studied in complementary reactions, like pp hard scattering and Drell-Yan processes. In particular the Sivers TMD PDF, which encodes the correlation between the nucleon spin and quark transverse momentum and appears in the Sivers Transverse Spin Asymmetry (TSA), is expected to have opposite sign in DY and SIDIS. In 2015 COMPASS measured for the first time the Drell-Yan reaction pi- p\u2191 \u2192 mu- mu X to test this prediction and the results have been recently published. The main topic of the thesis is the first measurement of the TSAs weighted with the dimuon transverse momentum in this data. These asymmetries complement the conventional TSAs and their advantage is that they do not contain convolutions over intrinsic transverse momenta. My analysis work is described in detail and the results are compared with calculations based on the extraction of the Sivers function from the recently measured weighted Sivers asymmetry in SIDIS. The thesis also contains a theoretical introduction, the description of the apparatus focused on the polarised target and its monitoring system to which I contributed. Finally, a chapter dedicated to the first original analysis in my PhD, the measurement of a Sivers-like asymmetry in the J/psit production in SIDIS, which is related to the gluon Sivers function, is included as well

Multiplicities of charged kaons from deep-inelastic muon scattering off an isoscalar target

Precise measurements of charged-kaon multiplicities in deep inelastic scattering were performed. The results are presented in three-dimensional bins of the Bjorken scaling variable x, the relative virtual-photon energy y, and the fraction z of the virtual-photon energy carried by the produced hadron. The data were obtained by the COMPASS Collaboration by scattering 160 GeV muons off an isoscalar 6LiD target. They cover the kinematic domain View the MathML source in the photon virtuality, 0.0045 GeV/c2 in the invariant mass of the hadronic system. The results from the sum of the z -integrated K+ and K 12 multiplicities at high x point to a value of the non-strange quark fragmentation function larger than obtained by the earlier DSS fit

Blood Arsenic Levels as a Marker of Breast Cancer Risk among BRCA1 Carriers

Funding Information: Funding: The study was funded by the National Centre for Research and Development Projects. INNOMED/1/16/NCBR/2014 and PBS3/B7/26/2015. Publisher Copyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland.An important group of breast cancers is those associated with inherited susceptibility. In women, several predisposing mutations in genes involved in DNA repair have been discovered. Women with a germline pathogenic variant in BRCA1 have a lifetime cancer risk of 70%. As part of a larger prospective study on heavy metals, our aim was to investigate if blood arsenic levels are associated with breast cancer risk among women with inherited BRCA1 mutations. A total of 1084 participants with pathogenic variants in BRCA1 were enrolled in this study. Subjects were followed from 2011 to 2020 (mean follow-up time: 3.75 years). During that time, 90 cancers were diagnosed, including 67 breast and 10 ovarian cancers. The group was stratified into two categories (lower and higher blood As levels), divided at the median (<0.85 µg/L and ≥0.85 µg/L) As level among all unaffected participants. Cox proportional hazards models were used to model the association between As levels and cancer incidence. A high blood As level (≥0.85 µg/L) was associated with a significantly increased risk of developing breast cancer (HR = 2.05; 95%CI: 1.18–3.56; p = 0.01) and of any cancer (HR = 1.73; 95%CI: 1.09–2.74; p = 0.02). These findings suggest a possible role of environmental arsenic in the development of cancers among women with germline pathogenic variants in BRCA1.Peer reviewe

Proceedings of Abstracts, School of Physics, Engineering and Computer Science Research Conference 2022

© 2022 The Author(s). This is an open-access work distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. For further details please see https://creativecommons.org/licenses/by/4.0/. Plenary by Prof. Timothy Foat, ‘Indoor dispersion at Dstl and its recent application to COVID-19 transmission’ is © Crown copyright (2022), Dstl. This material is licensed under the terms of the Open Government Licence except where otherwise stated. To view this licence, visit http://www.nationalarchives.gov.uk/doc/open-government-licence/version/3 or write to the Information Policy Team, The National Archives, Kew, London TW9 4DU, or email: [email protected] present proceedings record the abstracts submitted and accepted for presentation at SPECS 2022, the second edition of the School of Physics, Engineering and Computer Science Research Conference that took place online, the 12th April 2022

Collins and Sivers asymmetries in muonproduction of pions and kaons off transversely polarised protons

Measurements of the Collins and Sivers asymmetries for charged pions and charged and neutral kaons produced in semi-inclusive deep-inelastic scattering of high energy muons off transversely polarised protons are presented. The results were obtained using all the available COMPASS proton data, which were taken in the years 2007 and 2010. The Collins asymmetries exhibit in the valence region a non-zero signal for pions and there are hints of non-zero signal also for kaons. The Sivers asymmetries are found to be positive for positive pions and kaons and compatible with zero otherwise. © 2015