Related papers: Transversity and $\Lambda$ polarization at COMPASS

Probing transversity by measuring $\Lambda$ polarisation in SIDIS

Based on the observation of sizeable target-transverse-spin asymmetries in single-hadron and hadron-pair production in Semi-Inclusive measurements of Deep Inelastic Scattering (SIDIS), the chiral-odd transversity quark distribution…

High Energy Physics - Experiment · Physics 2021-12-15 M. G. Alexeev , G. D. Alexeev , A. Amoroso , V. Andrieux , V. Anosov , K. Augsten , W. Augustyniak , C. D. R. Azevedo , B. Badelek , F. Balestra , M. Ball , J. Barth , R. Beck , Y. Bedfer , J. Berenguer Antequera , J. Bernhard , M. Bodlak , F. Bradamante , A. Bressan , V. E. Burtsev , W. -C. Chang , C. Chatterjee , M. Chiosso , A. G. Chumakov , S. -U. Chung , A. Cicuttin , P. M. M. Correia , M. L. Crespo , D. D'Ago , S. Dalla Torre , S. S. Dasgupta , S. Dasgupta , I. Denisenko , O. Yu. Denisov , S. V. Donskov , N. Doshita , Ch. Dreisbach , W. Duennweber , R. R. Dusaev , A. Efremov , P. D. Eversheim , P. Faccioli , M. Faessler , A. Ferrero , M. Finger , M. Finger , H. Fischer , C. Franco , J. M. Friedrich , V. Frolov , L. G. Garcia Ordonez , F. Gautheron , O. P. Gavrichtchouk , S. Gerassimov , J. Giarra , I. Gnesi , D. Giordano , M. Gorzellik , A. Grasso , A. Gridin , M. Grosse Perdekamp , B. Grube , A. Guskov , D. von Harrach , R. Heitz , N. Horikawa , N. d'Hose , C. -Y. Hsieh , S. Huber , S. Ishimoto , A. Ivanov , T. Iwata , M. Jandek , T. Jary , R. Joosten , E. Kabuss , D. H. Kang , F. Kaspar , A. Kerbizi , B. Ketzer , G. V. Khaustov , Yu. A. Khokhlov , Yu. Kisselev , F. Klein , J. H. Koivuniemi , V. N. Kolosov , I. Konorov , V. F. Konstantinov , A. M. Kotzinian , O. M. Kouznetsov , A. Koval , Z. Kral , F. Krinner , Y. Kulinich , F. Kunne , K. Kurek , R. P. Kurjata , A. Kveton , K. Lavickova , S. Levorato , Y. -S. Lian , J. Lichtenstadt , P. -J. Lin , R. Longo , V. E. Lyubovitskij , A. Maggiora , A. Magnon , N. Makins , N. Makke , G. K. Mallot , A. Maltsev , S. A. Mamon , B. Marianski , A. Martin , J. Marzec , J. Matousek , T. Matsuda , G. Mattson , G. V. Meshcheryakov , M. Meyer , W. Meyer , Yu. V. Mikhailov , M. Mikhasenko , E. Mitrofanov , Y. Miyachi , A. Moretti , A. Nagaytsev , C. Naim , T. S. Negrini , D. Neyret , J. Novy , W. -D. Nowak , G. Nukazuka , A. S. Nunes , A. G. Olshevskiy , M. Ostrick , D. Panzieri , B. Parsamyan , S. Paul , H. Pekeler , J. -C. Peng , M. Pesek , D. V. Peshekhonov , M. Peskova , N. Pierre , S. Platchkov , J. Pochodzalla , V. A. Polyakov , J. Pretz , M. Quaresma , C. Quintans , G. Reicherz , C. Riedl , T. Rudnicki , D. I. Ryabchikov , A. Rymbekova , A. Rychter , V. D. Samoylenko , A. Sandacz , S. Sarkar , I. A. Savin , G. Sbrizzai , P. Schiavon , H. Schmieden , A. Selyunin , K. Sharko , L. Sinha , M. Slunecka , J. Smolik , F. Sozzi , A. Srnka , D. Steffen , M. Stolarski , O. Subrt , M. Sulc , H. Suzuki , P. Sznajder , S. Tessaro , F. Tessarotto , A. Thiel , J. Tomsa , F. Tosello , A. Townsend , V. Tskhay , S. Uhl , A. Vauth , B. M. Veit , J. Veloso , B. Ventura , A. Vidon , M. Virius , M. Wagner , S. Wallner , K. Zaremba , P. Zavada , M. Zavertyaev , M. Zemko , E. Zemlyanichkina , Y. Zhao , M. Ziembicki

Transverse Lambda polarization in unpolarized semi-inclusive DIS

The long-standing problem of transverse Lambda polarization in high-energy collisions of unpolarized hadrons can be tackled by considering new, spin and k_T-dependent quark fragmentation functions for an unpolarized quark into a polarized,…

High Energy Physics - Phenomenology · Physics 2015-06-25 M. Anselmino , D. Boer , U. D'Alesio , F. Murgia

Measurements of transverse-momentum dependent effects in semi-inclusive DIS at COMPASS

Its cornerstone were studies of hadron production in deep inelastic scattering (DIS), which can be interpreted in the transverse-momentum-dependent (TMD) factorisation framework, allowing to access the distributions of polarisation and…

High Energy Physics - Experiment · Physics 2026-05-13 Jan Matousek

Transverse Spin and Transverse Momentum Effects at COMPASS

The investigation of transverse spin and transverse momentum effects in deep inelastic scattering is one of the key physics programs of the COMPASS collaboration. In the years 2002-2004 COMPASS took data scattering 160 GeV muons on a…

High Energy Physics - Experiment · Physics 2019-08-13 C. Schill

Transversity and Lambda polarization

Two related issues are discussed, which might be easily explored by present and future COMPASS experiments. The first one deals with the new world of transversity, the fundamental polarized parton distribution so far totally unknown. The…

High Energy Physics - Phenomenology · Physics 2007-05-23 Mauro Anselmino

Transverse Spin Physics at COMPASS

The investigation of transverse spin and transverse momentum effects in deep inelastic scattering is one of the key physics programs of the COMPASS collaboration. Three channels have been analyzed at COMPASS to access the transversity…

High Energy Physics - Experiment · Physics 2019-08-13 Christian Schill

Transverse Spin Effects at COMPASS

The investigation of transverse spin and transverse momentum effects in deep inelastic scattering is one of the key physics programs of the COMPASS collaboration. In the years 2002-2004 COMPASS took data scattering 160 GeV muons on a…

High Energy Physics - Experiment · Physics 2011-01-13 C. Schill

Recent COMPASS results on Transverse Spin Asymmetries in SIDIS

After reviewing the most important COMPASS results on transverse spin effects in SIDIS, I will present the recent work we have done on weighted Sivers asymmetries and "transversity induced" $\Lambda$ polarisation. Using the high statistics…

High Energy Physics - Experiment · Physics 2018-02-14 Franco Bradamante

Probing the transverse spin of quarks in deep inelastic scattering

To identify some way to measure the quark transversity, this thesis analyzes one-particle and two-particle inclusive deep inelastic scattering, where one and two of the outgoing hadrons are detected in coincidence with the electron. It is…

High Energy Physics - Phenomenology · Physics 2009-09-29 A. Bacchetta

Measurement of transverse polarization of $\Lambda$ and $\bar{\Lambda}$ hyperons inside jets in $pp$ collisions at $\sqrt{s}=200$ GeV

A surprisingly large transverse polarization of $\Lambda$ hyperons in unpolarized hadron-nucleon/nucleus collisions has been observed for 50 years, and the origin of this polarization remains an important open question. Recently,…

High Energy Physics - Experiment · Physics 2026-05-14 STAR Collaboration , B. E. Aboona , J. Adam , G. Agakishiev , I. Aggarwal , M. M. Aggarwal , Z. Ahammed , A. Aitbayev , I. Alekseev , E. Alpatov , A. K. Alshammri , A. Aparin , S. Aslam , J. Atchison , G. S. Averichev , V. Bairathi , X. Bao , P. Barik , K. Barish , S. Behera , P. Bhaga t , A. Bhasin , S. Bhatta , I. G. Bordyuzhin , J. D. Brandenburg , A. V. Brandin , C. Broodo , X. Z. Cai , H. Caines , M. Calderón de la Barca Sánchez , D. Cebra , J. Ceska , I. Chakaberia , Y. S. Chang , Z. Chang , A. Chatterjee , D. Chen , J. H. Chen , L. Chen , Q. Chen , W. Chen , Z. Chen , J. Cheng , Y. Cheng , W. Christie , X. Chu , S. Corey , H. J. Crawford , G. Dale-Gau , A. Das , D. De Souza Lemos , T. G. Dedovich , I. M. Deppner , A. A. Derevschikov , A. Deshpande , A. Dhamija , A. Dimri , P. Dixit , X. Dong , J. L. Drachenberg , E. Duckworth , J. C. Dunlop , Y. S. El-Feky , J. Engelage , G. Eppley , S. Esumi , O. Evdokimov , O. Eyser , B. Fan , Y. Fang , R. Fatemi , S. Fazio , H. Feng , Y. Feng , E. Finch , Y. Fisyak , F. A. Flor , B. Fu , C. Fu , T. Fu , T. Gao , Y. Gao , G. Garcia , F. Geurts , A. Gibson , A. Giri , K. Gopal , M. Gor don , X. Gou , D. Grosnick , A. Gu , J. Gu , A. Gupta , A. Hamed , R. J. Hamilton , J. Han , X. Han , M. D. Harasty , J. W. Harris , H. Harrison-Smith , L. B. Havener , X. H. He , Y. He , C. Hu , Q. Hu , Y. Hu , H. Huang , H. Z. Huang , S. L. Huang , T. Huang , Y. Huang , Y. Huang , Y. Huan g , M. Isshiki , W. W. Jacobs , A. Jalotra , C. Jena , Y. Ji , J. Jia , X. Jiang , C. Jin , Y. Jin , N. Jindal , X. Ju , E. G. Judd , S. Kabana , D. Kalinkin , J. Kang , K. Kang , A. R. Kanuganti , D. Kapukchyan , K. Kauder , D. Keane , A. Kechechyan , M. Kesler , A. Khanal , A. Khanal , J. Kim , A. Kiselev , A. G. Knospe , L. Kochenda , Y. Kong , A. A. Korobitsin , B. Korodi , A. Yu. Kraeva , P. Kravtsov , L. Kumar , M. C. Labonte , R. Lacey , J. M. Landgraf , C. Larson , A. Lebedev , R. Lednicky , J. H. Lee , Y. H. Leung , C. Li , D. Li , H-S. Li , H. Li , H. Li , H. Li , W. Li , X. Li , X. Li , Y. Li , Z. Li , Z. Li , X. Liang , T. Lin , Y. Lin , C. Liu , G. Liu , H. Liu , L. Liu , L. Liu , Z. Liu , Z. Liu , T. Ljubicic , O. Lomicky , E. M. Loyd , T. Lu , J. Luo , X. F. Luo , V. B. Luong , L. Ma , R. Ma , Y. G. Ma , N. Magdy , B. Maghoul , R. Manikandhan , O. M atonoha , K. Menduli , K. Mi , N. G. Minaev , B. Mohanty , B. Mondal , M. M. Mondal , I. Mooney , D. A. Morozov , M. I. Nagy , C. J. Naim , A. S. Nain , J. D. Nam , M. Nasim , H. Nasrulloh , E. Nedorezov , J. M. Nelson , M. Nie , G. Nigmatkulov , T. Niida , L. V. Nogach , T. Nonaka , G. Odyniec , A. Ogawa , S. Oh , V. A. Okorokov , K. Okubo , B. S. Page , M. Pal , S. Pal , A. Pandav , A. Panday , A. K. Pandey , Y. Panebratsev , T. Pani , P. Parfenov , A. Paul , S. Paul , C. Perkins , S. Ping , I. D. Ponce Pinto , M. Posik , E. Pottebaum , A. Povarov , S. Prodhan , T. L. Protzman , N. K. Pruthi , J. Putschke , Y. Qi , Z. Qin , H. Qiu , S. K. Radhakrishnan , A. Rana , R. L. Ray , C. W. Robertson , O. V. Rogachevsky , M. A. Rosales Aguilar , D. Roy , L. Ruan , A. K. Sahoo , N. R. Sahoo , H. Sako , S. Salur , S. S. Sambyal , E. Samigullin , D. T. Samuel , J. K. Sandhu , S. Sato , B. C. Schaefer , N. Schmitz , J. Seger , R. Seto , P. Seyboth , N. Shah , E. Shahaliev , P. V. Shanmuganathan , T. Shao , M. Sharma , N. Sharma , R. Sharma , S. R. Sharma , A. I. Sheikh , D. Shen , D. Y. Shen , K. Shen , S. Shi , Y. Shi , Shilpa , E. Shulga , F. S , J. Singh , S. Singha , P. Sinha , M. J. Skoby , Y. Söhngen , Y. Song , T. D. S. Stanislaus , M. Strikhanov , Y. Su , X. Sun , Y. Sun , B. Surrow , D. N. Svirida , Z. W. Sweger , A. C. Tamis , A. H. Tang , Z. Tang , A. Taranenko , T. Tarnowsky , J. H. Thomas , A. Timofeev , D. Tl usty , M. V. Tokarev , D. Torres-Valladares , S. Trentalange , O. D. Tsai , C. Y. Tsang , Z. Tu , J. E. Tyler , T. Ullrich , D. G. Underwood , G. Van Buren , A. N. Vasiliev , F. Videbæk , S. Vokal , S. A. Voloshin , F. Wang , G. Wang , G. Wang , J. S. Wang , J. Wang , K. Wang , X. W ang , Y. Wang , Y. Wang , Y. Wang , Z. Wang , Z. Wang , Z. Wang , J. C. Webb , P. C. Weidenkaff , G. D. Westfall , H. Wieman , G. Wilks , S. W. Wissink , C. P. Wong , J. Wu , X. Wu , X. Wu , X. Wu , B. Xi , Y. Xiao , Z. G. Xiao , G. Xie , W. Xie , H. Xu , N. Xu , Q. H. Xu , X. Xu , Y. Xu , Y. Xu , Y. Xu , Y. Xu , Z. Xu , Z. Xu , G. Yan , Z. Yan , C. Yang , Q. Yang , S. Yang , Y. Yang , Z. Ye , Z. Ye , L. Yi , Y. Yu , W. Yuan , W. Zha , C. Zhang , D. Zhang , J. Zhang , K. Zhang , L. Zhang , S. Zhang , W. Zhang , W. Zhang , X. Zhang , Y. Zhang , Y. Zhang , Y. Zhang , Y. Zhang , Z. Zhan g , Z. Zhang , F. Zhao , J. Zhao , S. Zhou , Y. Zhou , C. Zhu , X. Zhu , M. Zurek , M. Zyzak

Transverse Spin Effects at COMPASS

Single spin asymmetries in semi-inclusive deep-inelastic scattering off transversely polarized nucleon targets have been under intense experimental investigation over the past few years. They provide new insights into QCD and the nucleon…

High Energy Physics - Experiment · Physics 2009-08-24 H. Wollny

$q \to \Lambda$ Fragmentation Function and Nucleon Transversity Distribution in a Diquark Model

Based on a simple quark-diquark model, we propose a set of unpolarized, longitudinally polarized and transversely polarized fragmentation functions for the $\Lambda$ by fitting the unpolarized $\Lambda$ production data in $e^+ e ^- $…

High Energy Physics - Phenomenology · Physics 2009-11-07 Jian-Jun Yang

Transverse Spin Physics at COMPASS

The study of transverse spin effects is part of the scientific program of COMPASS, a fixed target experiment at the CERN SPS. COMPASS investigates the transversity PDFs in semi-inclusive DIS, using a longitudinally polarized muon beam of…

High Energy Physics - Experiment · Physics 2019-08-13 Federica Sozzi

Transverse $\Lambda$ polarization in unpolarized $pp\rightarrow \, {\rm jet}\, \Lambda^\uparrow\, X $

In this Letter, we investigate the spontaneous transverse polarization of $\Lambda$ hyperons produced in unpolarized $pp$ collisions inside a jet, by adopting a TMD approach where transverse momentum effects are included only in the…

High Energy Physics - Phenomenology · Physics 2024-03-01 Umberto D'Alesio , Leonard Gamberg , Francesco Murgia , Marco Zaccheddu

Transverse Lambda polarization in inclusive processes

A formalism proposed to study transverse Lambda polarization in unpolarized hadronic processes, based on a generalized pQCD factorization theorem, is extended to semi-inclusive DIS. Analytical expressions and examples of numerical estimates…

High Energy Physics - Phenomenology · Physics 2009-11-07 M. Anselmino , D. Boer , U. D'Alesio , F. Murgia

New insight on the Sivers transverse momentum dependent distribution function

Polarised Semi-Inclusive Deep Inelastic Scattering (SIDIS) processes allow to study Transverse Momentum Dependent partonic distributions (TMDs), which reveal a non trivial three dimensional internal structure of the hadrons in momentum…

High Energy Physics - Phenomenology · Physics 2015-05-20 M. Anselmino , M. Boglione , U. D'Alesio , S. Melis , F. Murgia , A. Prokudin

Transversity and Collins functions from SIDIS and e+e- data

A global analysis of the experimental data on azimuthal asymmetries in semi-inclusive deep inelastic scattering (SIDIS), from the HERMES and COMPASS Collaborations, and in e+e- --> h1 h2 X processes, from the BELLE Collaboration, is…

High Energy Physics - Phenomenology · Physics 2010-04-06 M. Anselmino , M. Boglione , U. D'Alesio , A. Kotzinian , F. Murgia , A. Prokudin , C. Turk

Transversity distributions from difference asymmetries in semi-inclusive DIS

In recent years information on the transversity distribution $h_1$ has been obtained combining the Collins asymmetry results from semi-inclusive deep inelastic scattering (SIDIS) data on transversely polarized nucleon targets with the…

High Energy Physics - Phenomenology · Physics 2019-06-12 V. Barone , F. Bradamante , A. Bressan , A. Kerbizi , A. Martin , A. Moretti , J. Matousek , G. Sbrizzai

How Could the Proton Transversity be Measured

The perspectives of two new nonstandard methods of transversal quark polarization measurement are considered: the jet handedness and the so-called "Collins effect" due to spin dependent T-odd fragmentation function responsible for the…

High Energy Physics - Phenomenology · Physics 2009-10-31 A. V. Efremov

Transverse Momentum Effects in Unpolarised SIDIS at COMPASS

Unpolarised semi-inclusive DIS is receiving a growing interest as a powerful tool to access poorly known universal functions that play a key role in many processes, in particular in the study of the spin structure of the nucleon. These…

High Energy Physics - Experiment · Physics 2015-06-23 Nour Makke