Single-Spin Asymmetry of Neutrons in Polarized <i>pA</i> Collisions
Absorptive corrections, which are known to suppress proton-neutron transitions with a large fractional momentum <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>z</mi><mo>→</mo>&...
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MDPI AG
2023-11-01
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| Online Access: | https://www.mdpi.com/2624-8174/5/4/68 |
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| author | Boris Z. Kopeliovich Irina K. Potashnikova Iván Schmidt |
| author_facet | Boris Z. Kopeliovich Irina K. Potashnikova Iván Schmidt |
| author_sort | Boris Z. Kopeliovich |
| collection | DOAJ |
| description | Absorptive corrections, which are known to suppress proton-neutron transitions with a large fractional momentum <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>z</mi><mo>→</mo><mn>1</mn></mrow></semantics></math></inline-formula> in <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>p</mi><mi>p</mi></mrow></semantics></math></inline-formula> collisions, become dramatically strong on a nuclear target, and they push the partial cross sections of leading neutron production to the very periphery of the nucleus. The mechanism of the pion <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mi>π</mi></semantics></math></inline-formula> and axial vector meson <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mi>a</mi><mn>1</mn></msub></semantics></math></inline-formula> interference, which successfully explains the observed single-spin asymmetry in a polarized <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>p</mi><mi>p</mi><mo>→</mo><mi>n</mi><mi>X</mi></mrow></semantics></math></inline-formula>, is extended to the collisions of polarized protons with nuclei. When corrected for nuclear effects, it explains the observed single-spin azimuthal asymmetry of neutrons that is produced in inelastic events, which is where the nucleus violently breaks up. This single-spin asymmetry is found to be negative and nearly atomic mass number <i>A</i>-independent. |
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| language | English |
| last_indexed | 2024-03-08T20:26:19Z |
| publishDate | 2023-11-01 |
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| series | Physics |
| spelling | doaj.art-ae7d4bdae7ce4070a4a2b057887dd07a2023-12-22T14:33:12ZengMDPI AGPhysics2624-81742023-11-01541048106010.3390/physics5040068Single-Spin Asymmetry of Neutrons in Polarized <i>pA</i> CollisionsBoris Z. Kopeliovich0Irina K. Potashnikova1Iván Schmidt2Departamento de Física, Universidad Técnica Federico Santa María, Avenida España 1680, Valparaíso 239-0123, ChileDepartamento de Física, Universidad Técnica Federico Santa María, Avenida España 1680, Valparaíso 239-0123, ChileDepartamento de Física, Universidad Técnica Federico Santa María, Avenida España 1680, Valparaíso 239-0123, ChileAbsorptive corrections, which are known to suppress proton-neutron transitions with a large fractional momentum <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>z</mi><mo>→</mo><mn>1</mn></mrow></semantics></math></inline-formula> in <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>p</mi><mi>p</mi></mrow></semantics></math></inline-formula> collisions, become dramatically strong on a nuclear target, and they push the partial cross sections of leading neutron production to the very periphery of the nucleus. The mechanism of the pion <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mi>π</mi></semantics></math></inline-formula> and axial vector meson <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><msub><mi>a</mi><mn>1</mn></msub></semantics></math></inline-formula> interference, which successfully explains the observed single-spin asymmetry in a polarized <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>p</mi><mi>p</mi><mo>→</mo><mi>n</mi><mi>X</mi></mrow></semantics></math></inline-formula>, is extended to the collisions of polarized protons with nuclei. When corrected for nuclear effects, it explains the observed single-spin azimuthal asymmetry of neutrons that is produced in inelastic events, which is where the nucleus violently breaks up. This single-spin asymmetry is found to be negative and nearly atomic mass number <i>A</i>-independent.https://www.mdpi.com/2624-8174/5/4/68neutron productionpion poleinterferencespin-flipazimuthal asymmetry |
| spellingShingle | Boris Z. Kopeliovich Irina K. Potashnikova Iván Schmidt Single-Spin Asymmetry of Neutrons in Polarized <i>pA</i> Collisions Physics neutron production pion pole interference spin-flip azimuthal asymmetry |
| title | Single-Spin Asymmetry of Neutrons in Polarized <i>pA</i> Collisions |
| title_full | Single-Spin Asymmetry of Neutrons in Polarized <i>pA</i> Collisions |
| title_fullStr | Single-Spin Asymmetry of Neutrons in Polarized <i>pA</i> Collisions |
| title_full_unstemmed | Single-Spin Asymmetry of Neutrons in Polarized <i>pA</i> Collisions |
| title_short | Single-Spin Asymmetry of Neutrons in Polarized <i>pA</i> Collisions |
| title_sort | single spin asymmetry of neutrons in polarized i pa i collisions |
| topic | neutron production pion pole interference spin-flip azimuthal asymmetry |
| url | https://www.mdpi.com/2624-8174/5/4/68 |
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