Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Properties of baryons in the chiral quark model
KTH, Superseded Departments, Physics.ORCID iD: 0000-0002-3525-8349
1997 (English)Licentiate thesis, comprehensive summary (Other scientific)
Abstract [en]

In this thesis, several properties of baryons are studied using the chiral quark model. The chiral quark model is a theory which can be used to describe low energy phenomena of baryons.

In Paper 1, the chiral quark model is studied using wave functions with configuration mixing. This study is motivated by the fact that the chiral quark model cannot otherwise break the Coleman–Glashow sum-rule for the magnetic moments of the octet baryons, which is xperimentally broken by about ten standard deviations. Configuration mixing with quark-diquark components is also able to reproduce the octet baryon magnetic moments very accurately.

In Paper 2, the chiral quark model is used to calculate the decuplet baryon magnetic moments. The values for the magnetic moments of the ++and− are in good agreement with the experimental results. The total quark spin polarizations are also calculated and are found to be significantly smaller than the non-relativistic quark model results.

In Paper 3, the weak form factors for semileptonic octet baryon decays are studied in the chiral quark model. The “weak magnetism” form factors are found to be consistent with the conserved vector current (CVC) results and the induced pseudotensor form factors, which seem to be model independent, are small. The results obtained are in general agreement with experiments and are also compared with other model calculations.

Place, publisher, year, edition, pages
Stockholm: KTH , 1997. , p. viii, 52
Series
Trita-FYS, ISSN 0280-316X ; 8026
Keywords [en]
Chiral quark model, baryons, configuration mixing, magnetic moments, Coleman-Glashow sum-rule, spin polarizations, weak form factors, semilepronic decays
National Category
Physical Sciences
Identifiers
URN: urn:nbn:se:kth:diva-756ISRN: KTH/FYS/TEO/R--97/9--SEISBN: 91-7170-211-3 (print)OAI: oai:DiVA.org:kth-756DiVA, id: diva2:14733
Note
QC 20100618Available from: 2000-09-26 Created: 2000-09-26 Last updated: 2011-06-20Bibliographically approved
List of papers
1. Octet baryon magnetic moments in the chiral quark model with configuration mixing
Open this publication in new window or tab >>Octet baryon magnetic moments in the chiral quark model with configuration mixing
1998 (English)In: Physical Review D. Particles and fields, ISSN 0556-2821, E-ISSN 1089-4918, Vol. 57, no 1, p. 452-464Article in journal (Refereed) Published
Abstract [en]

The Coleman-Glashow sum-rule for magnetic moments is always fulfilled in the chiral quark model, independently of SU(3) symmetry breaking. This is due to the structure of the wave functions, coming from the non-relativistic quark model. Experimentally, the Coleman-Glashow sum-rule is violated by about ten standard deviations. To overcome this problem, two models of wave functions with configuration mixing are studied. One of these models violates the Coleman-Glashow sum-rule to the right degree and also reproduces the octet baryon magnetic moments rather accurately.

Place, publisher, year, edition, pages
The American Physical Society, 1998
National Category
Subatomic Physics
Identifiers
urn:nbn:se:kth:diva-13372 (URN)10.1103/PhysRevD.57.452 (DOI)000071320700049 ()
Funder
Swedish Research Council, F-AA/FU03281-310
Note
QC 20100616Available from: 2011-06-21 Created: 2010-06-16 Last updated: 2017-12-12Bibliographically approved
2. Decuplet baryon magnetic moments in the chiral quark model
Open this publication in new window or tab >>Decuplet baryon magnetic moments in the chiral quark model
1998 (English)In: Physical Review D. Particles and fields, ISSN 0556-2821, E-ISSN 1089-4918, Vol. 57, no 9, p. 5916-5919Article in journal (Refereed) Published
Abstract [en]

We present calculations of the decuplet baryon magnetic moments in the chiral quark model. As input we use parameters obtained in qualitatively accurate fits to the octet baryon magnetic moments studied previously. The values found for the magnetic moments of Delta(++) and Omega(-) are in good agreement with experiments. We finally calculate the total quark spin polarizations of the decuplet baryons and find that they are considerably smaller than what is expected from the non-relativistic quark model.

Place, publisher, year, edition, pages
The American Physical Society, 1998
National Category
Subatomic Physics
Identifiers
urn:nbn:se:kth:diva-13377 (URN)10.1103/PhysRevD.57.5916 (DOI)000073464200066 ()
Funder
Swedish Research Council, F-AA/FU03281-310
Note
QC 20100616Available from: 2011-06-21 Created: 2010-06-16 Last updated: 2017-12-12Bibliographically approved
3. Weak form factors for semileptonic octet baryon decays in the chiral quark model
Open this publication in new window or tab >>Weak form factors for semileptonic octet baryon decays in the chiral quark model
1999 (English)In: European Physical Journal C, ISSN 1434-6044, E-ISSN 1434-6052, Vol. 6, no 2, p. 285-296Article in journal (Refereed) Published
Abstract [en]

We study the weak vector and axial-vector form factors of first- and second-class currents for the semileptonic octet baryon decays in the spirit of the chiral quark model. Our results for the weak magnetism form factors are consistent with the conserved vector current (CVC) results. The induced pseudotensor form factors, which are highly model dependent. are small. The overall performance of the chiral quark model is quite good and in general agreement with existing experimental data.

Place, publisher, year, edition, pages
Springer-Verlag, 1999
National Category
Subatomic Physics
Identifiers
urn:nbn:se:kth:diva-13374 (URN)10.1007/s100529800908 (DOI)000077853000007 ()
Funder
Swedish Research Council, F-AA/FU03281-310
Note
QC 20100616Available from: 2011-06-21 Created: 2010-06-16 Last updated: 2017-12-12Bibliographically approved

Open Access in DiVA

fulltext(481 kB)608 downloads
File information
File name FULLTEXT01.pdfFile size 481 kBChecksum
Type fulltextMimetype application/pdf
errata(19 kB)35 downloads
File information
File name ERRATA01.pdfFile size 19 kBChecksum
Type errataMimetype application/pdf

Search in DiVA

By author/editor
Ohlsson, Tommy
By organisation
Physics
Physical Sciences

Search outside of DiVA

GoogleGoogle Scholar
Total: 608 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

isbn
urn-nbn

Altmetric score

isbn
urn-nbn
Total: 166 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf