ترغب بنشر مسار تعليمي؟ اضغط هنا

Impact of LHCb 13 TeV $W$ and $Z$ pseudo-data on the Parton Distribution Functions

58   0   0.0 ( 0 )
 نشر من قبل Hang Yin
 تاريخ النشر 2020
  مجال البحث
والبحث باللغة English




اسأل ChatGPT حول البحث

We study the potential of the LHCb 13 TeV single $W^{pm}$ and $Z$ boson pseudo-data for constraining the parton distribution functions (PDFs) of the proton. As an example, we demonstrate the sensitivity of the LHCb 13 TeV data, collected with integrated luminosities of 5 fb$^{-1}$ and 300 fb$^{-1}$, to reducing the PDF uncertainty bands of the CT14HERA2 PDFs, using the error PDF updating package {sc ePump}. The sensitivities of various experimental observables are compared. Generally, sizable reductions in PDF uncertainties can be observed in the 300 fb$^{-1}$ data sample, particularly in the small-$x$ region. The double-differential cross section measurement of $Z$ boson $p_T$ and rapidity can greatly reduce the uncertainty bands of $u$ and $d$ quarks in almost the whole $x$ range, as compared to various single observable measurements.



قيم البحث

اقرأ أيضاً

112 - Anatoly Radyushkin 2018
We incorporate recent calculations of one-loop corrections for the reduced Ioffe-time pseudo-distribution ${mathfrak M} ( u,z_3^2)$ to extend the leading-logarithm analysis of lattice data obtained by Orginos et al. We observe that the one-loop corre ctions contain a large term reflecting the fact that effective distances involved in the most important diagrams are much smaller than the nominal distance $z_3$. The large correction in this case may be absorbed into the evolution term, and the perturbative expansion used for extraction of parton densities at the $mu approx 2$ GeV scale is under control. The extracted parton distribution is rather close to global fits in the $x>0.1$ region, but deviates from them for $x<0.1$.
The impact of recent measurements of heavy-flavour production in deep inelastic $ep$ scattering and in $pp$ collisions on parton distribution functions is studied in a QCD analysis in the fixed-flavour number scheme at next-to-leading order. Differen tial cross sections of charm- and beauty-hadron production measured by LHCb are used together with inclusive and heavy-flavour production cross sections in deep inelastic scattering at HERA. The heavy-flavour data of the LHCb experiment impose additional constraints on the gluon and the sea-quark distributions at low partonic fractions $x$ of the proton momentum, down to $x sim 5 times 10^{-6}$. This kinematic range is currently not covered by other experimental data in perturbative QCD fits.
Initial state evolution in parton shower event generators involves parton distribution functions. We examine the probability for the system to evolve from a higher scale to a lower scale without an initial state splitting. A simple argument suggests that this probability, when multiplied by the ratio of the parton distributions at the two scales, should be independent of the parton distribution functions. We call this the PDF property. We examine whether the PDF property actually holds using Pythia and Deductor. We also test a related property for the Deductor shower and discuss the physics behind the results.
104 - Jiri Chyla 2007
The organization of finite order QCD approximations to $F_2^{gamma}(x,Q^2)$ based on the separation of pure QED contribution from those of genuine QCD nature is discussed.
84 - X. G. Wang , A. W. Thomas 2019
We explore the application of a two-component model of proton structure functions in the analysis of deep-inelastic scattering (DIS) data at low $Q^2$ and small $x$. This model incorporates both vector meson dominance and the correct photo-production limit. The CJ15 parameterization is applied to the QCD component, in order to take into account effects of order $1/Q^2$ effects, such as target mass corrections and higher twist contributions. The parameters of the leading twist parton distribution functions and higher twist coefficient functions are determined by fitting deep inelastic scattering data. The second moments of the parton distribution functions are extracted and compared with other global fits and lattice determinations.
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