592 research outputs found
The resummation of inter-jet energy flow for gaps-between-jets processes at HERA
We calculate resummed perturbative predictions for gaps-between-jets
processes and compare to HERA data. Our calculation of this non-global
observable needs to include the effects of primary gluon emission (global
logarithms) and secondary gluon emission (non-global logarithms) to be correct
at the leading logarithm (LL) level. We include primary emission by calculating
anomalous dimension matrices for the geometry of the specific event definitions
and estimate the effect of non-global logarithms in the large limit. The
resulting predictions for energy flow observables are consistent with
experimental data.Comment: 31 pages, 4 figures, 2 table
Energy Flow in Interjet Radiation
We study the distribution of transverse energy, Q_Omega, radiated into an
arbitrary interjet angular region, Omega, in high-p_T two-jet events. Using an
approximation that emphasizes radiation directly from the partons that undergo
the hard scattering, we find a distribution that can be extrapolated smoothly
to Q_Omega=Lambda_QCD, where it vanishes. This method, which we apply
numerically in a valence quark approximation, provides a class of predictions
on transverse energy radiated between jets, as a function of jet energy and
rapidity, and of the choice of the region Omega in which the energy is
measured. We discuss the relation of our approximation to the radiation from
unobserved partons of intermediate energy, whose importance was identified by
Dasgupta and Salam.Comment: 26 pages, 8 eps figures. Revised to include a discussion of
non-global logarithm
Dijet Rapidity Gaps in Photoproduction from Perturbative QCD
By defining dijet rapidity gap events according to interjet energy flow, we
treat the photoproduction cross section of two high transverse momentum jets
with a large intermediate rapidity region as a factorizable quantity in
perturbative QCD. We show that logarithms of soft gluon energy in the interjet
region can be resummed to all orders in perturbation theory. The resummed cross
section depends on the eigenvalues of a set of soft anomalous dimension
matrices, specific to each underlying partonic process, and on the
decomposition of the scattering according to the possible patterns of hard
color flow. We present a detailed discussion of both. Finally, we evaluate
numerically the gap cross section and gap fraction and compare the results with
ZEUS data. In the limit of low gap energy, good agreement with experiment is
obtained.Comment: 37 pages, Latex, 17 figure
Outstanding problems in the phenomenology of hard diffractive scattering
This paper is a summary of the discussion within the Diffractive and Low-x
Physics Working Group at the 1999 Durham Collider Workshop of the
interpretation of the Tevatron and HERA measurements of inclusive hard
diffraction.Comment: 5 pages, 1 figure. Talks and discussions from the UK Phenomenology
Workshop on Collider Physics, Durham, September 199
Accuracy of elastic fusion biopsy in daily practice: results of a multicenter study of 2115 patients
OBJECTIVES:
To assess the accuracy of Koelis fusion biopsy for the detection of prostate cancer and clinically significant prostate cancer in the everyday practice.
METHODS:
We retrospectively enrolled 2115 patients from 15 institutions in four European countries undergoing transrectal Koelis fusion biopsy from 2010 to 2017. A variable number of target (usually 2-4) and random cores (usually 10-14) were carried out, depending on the clinical case and institution habits. The overall and clinically significant prostate cancer detection rates were assessed, evaluating the diagnostic role of additional random biopsies. The cancer detection rate was correlated to multiparametric magnetic resonance imaging features and clinical variables.
RESULTS:
The mean number of targeted and random cores taken were 3.9 (standard deviation 2.1) and 10.5 (standard deviation 5.0), respectively. The cancer detection rate of Koelis biopsies was 58% for all cancers and 43% for clinically significant prostate cancer. The performance of additional, random cores improved the cancer detection rate of 13% for all cancers (P < 0.001) and 9% for clinically significant prostate cancer (P < 0.001). Prostate cancer was detected in 31%, 66% and 89% of patients with lesions scored as Prostate Imaging Reporting and Data System 3, 4 and 5, respectively. Clinical stage and Prostate Imaging Reporting and Data System score were predictors of prostate cancer detection in multivariate analyses. Prostate-specific antigen was associated with prostate cancer detection only for clinically significant prostate cancer.
CONCLUSIONS:
Koelis fusion biopsy offers a good cancer detection rate, which is increased in patients with a high Prostate Imaging Reporting and Data System score and clinical stage. The performance of additional, random cores seems unavoidable for correct sampling. In our experience, the Prostate Imaging Reporting and Data System score and clinical stage are predictors of prostate cancer and clinically significant prostate cancer detection; prostate-specific antigen is associated only with clinically significant prostate cancer detection, and a higher number of biopsy cores are not associated with a higher cancer detection rate
On the breaking of collinear factorization in QCD
We investigate the breakdown of collinear factorization for non-inclusive
observables in hadron-hadron collisions. For pure QCD processes, factorization
is violated at the three-loop level and it has a structure identical to that
encountered previously in the case of super-leading logarithms. In particular,
it is driven by the non-commutation of Coulomb/Glauber gluon exchanges with
other soft exchanges. Beyond QCD, factorization may be violated at the two-loop
level provided that the hard subprocess contains matrix element contributions
with phase differences between different colour topologies.Comment: Version 2: minor improvements for journal publicatio
Total cross-section and rapidity gap survival probability at the LHC through an eikonal with soft gluon resummation
New results are presented for total
cross-sections, in the framework of our QCD based model (GGPS). This is an
improved eikonal mini-jet model, where soft gluon radiation tames the fast
energy rise normally present in mini-jet models. We discuss the variability in
our predictions and provide a handy parametrization of our results for the LHC.
We find that our model predictions span the range . While this matches nicely with the range of most other
models, it does not agree with recent ones which include a "hard" Pomeron, even
though our model does include hard scattering. We compute the survival
probability for Large Rapidity Gap (LRG) events at the LHC and at the Tevatron.
These events are relevant, for example, for Higgs signal in the fusion
process. We also explore whether measurements of the total cross-sections at
the LHC can help us sharpen the model parameters and hence estimates for these
survival probabilities, further.Comment: 15 pages, 3 figures, LaTe
The impact of single-use digital flexible cystoscope for double J removal on hospital costs and work organization: A multicentric evaluation
External validation of the preoperative Karakiewicz nomogram in a large multicentre series of patients with renal cell carcinoma
External validation of the preoperative Karakiewicz nomogram in a large multicentre series of patients with renal cell carcinoma
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