ترغب بنشر مسار تعليمي؟ اضغط هنا

Cross Sections for the $gamma p to K^{*0}Sigma^+$ Reaction at $E_gamma = 1.7 - 3.0$ GeV

88   0   0.0 ( 0 )
 نشر من قبل Kenneth Hicks
 تاريخ النشر 2007
  مجال البحث
والبحث باللغة English




اسأل ChatGPT حول البحث

Differential cross sections for the reaction $gamma p to K^{*0} Sigma^+$ are presented at nine bins in photon energy in the range from 1.7 to 3.0 GeV. The kstar was detected by its decay products, $K^+pi^-$, in the CLAS detector at Jefferson Lab. These data are the first kstar photoproduction cross sections ever published over a broad range of angles. Comparison with a theoretical model based on the vector and tensor $K^*$-quark couplings shows good agreement with the data in general, after adjusting the models two parameters in a fit to our data. Disagreement between the data at forward angles and the global angle-energy fit to the model suggests that the role of scalar $kappa$ meson exchange in $t$-channel diagrams should be investigated.



قيم البحث

اقرأ أيضاً

Photon beam asymmetry $Sigma$ measurements for $omega$ photoproduction in the reaction $vec{gamma} p to omega p$ are reported for photon energies from 1.152 to 1.876 GeV. Data were taken using a linearly-polarized tagged photon beam, a cryogenic hydr ogen target, and the CLAS spectrometer in Hall B at Jefferson Lab. The measurements obtained markedly increase the size of the database for this observable, extend coverage to higher energies, and resolve discrepancies in previously published data. Comparisons of these new results with predictions from a chiral-quark-based model and from a dynamical coupled-channels model indicate the importance of interferences between $t$-channel meson exchange and $s$- and $u$-channel contributions, underscoring sensitivity to the nucleon resonances included in those descriptions. Comparisons with the Bonn-Gatchina partial-wave analysis indicate the $Sigma$ data reported here help to fix the magnitudes of the interference terms between the leading amplitudes in that calculation (Pomeron exchange and the resonant portion of the $J^P=3/2^+$ partial wave), as well as the resonant portions of the smaller partial waves with $J^P$= $1/2^-$, $3/2^-$, and $5/2^+$.
173 - I. Schulday , R. Lawall , J. Barth 2010
The reactions $gamma p rightarrow K^{+}Sigma^{pm}pi^{mp}$ were studied with the SAPHIR detector using a tagged photon beam at the electron stretcher facility ELSA in Bonn. The decays $Sigma^{-} rightarrow npi^{-}$ and $Sigma^{+} rightarrow npi^{+}, p pi^0$ were fully reconstructed. Reaction cross sections were measured as a function of the photon energy from threshold up to $2.6,$GeV with considerably improved statistics compared to a previous bubble chamber measurement. The cross sections rise monotonously with increasing photon energy. The two-particle mass distributions of $Sigma^{pm}pi^{mp}$ and $K^+pi^-$ show substantial production of resonant states.
A search for $K^-pp$ bound state (the lightest kaonic nucleus) has been performed using the $gamma d rightarrow K^+ pi^- rm{X}$ reaction at E$_gamma$=1.5-2.4 GeV at LEPS/SPring-8. The differential cross section of $K^+ pi^-$ photo-production off deut erium has been measured for the first time in this energy region, and a bump structure was searched for in the inclusive missing mass spectrum. A statistically significant bump structure was not observed in the region from 2.22 to 2.36 GeV/$c^2$, and the upper limits of the differential cross section for the $K^-pp$ bound state production were determined to be 0.1$-$0.7 $mu$ b (95$%$ confidence level) for a set of assumed binding energy and width values.
221 - K. Hicks , D. Keller , H. Kohri 2008
The $Sigma(1385)$ resonance, or $Sigma^*$, is well-known as part of the standard baryon decuplet with spin $J=3/2$. Measurements of the reaction $gamma p to K^+ Sigma^{*0}$ are difficult to extract due to overlap with the nearby $Lambda(1405)$ resona nce. However, the reaction $gamma n to K^+ Sigma^{*-}$ has no overlap with the $Lambda(1405)$ due to its charge. Here we report the first measurement of cross sections and beam asymmetries for photoproduction of the sigs from a deuteron target. % where the $K^+$ and $pi^-$ are detected in the LEPS spectrometer. The cross sections at forward angles range from 0.4 to 1.2 $mu$b, with a broad maximum near $E_gamma simeq 1.8$ GeV. The beam asymmetries are negative, in contrast to postive values for the $gamma n to K^+Sigma^-$ reaction.
التعليقات
جاري جلب التعليقات جاري جلب التعليقات
سجل دخول لتتمكن من متابعة معايير البحث التي قمت باختيارها
mircosoft-partner

هل ترغب بارسال اشعارات عن اخر التحديثات في شمرا-اكاديميا