Soft gluons and gauge-invariant subtractions in NLO parton-shower Monte Carlo event generators

We address the problem of decomposing graphs in perturbative QCD into terms associated with particular regions. Motivated by asking how to incorporate next-to-leading order (NLO) QCD corrections in parton-shower algorithms, we require that: (a) The integrand for the hard part is to be integrable even if the corrections are applied to a process that is not infrared and collinear safe. (b) The splitting between the terms should be defined gauge-invariantly. (c) The dependence on cut-offs should obey homogeneous evolution equations. In the context of one-gluon-emission graphs for deep inelastic scattering, we explain a subtractive technique that is based on gauge-invariant Wilson-line operators. Appropriate organization of subtractions involving the soft region allows a connection to previous work where evolution equations with respect to the directions of the Wilson lines have been derived.Comment: 11 pages, 2 figures; v2: comments and references added, results unchange

Calculation of TMD Evolution for Transverse Single Spin Asymmetry Measurements

The Sivers transverse single spin asymmetry (TSSA) is calculated and compared at different scales using the TMD evolution equations applied to previously existing extractions. We apply the Collins-Soper-Sterman (CSS) formalism, using the version recently developed by Collins. Our calculations rely on the universality properties of TMD-functions that follow from the TMD-factorization theorem. Accordingly, the non-perturbative input is fixed by earlier experimental measurements, including both polarized semi-inclusive deep inelastic scattering (SIDIS) and unpolarized Drell-Yan (DY) scattering. It is shown that recent COMPASS measurements are consistent with the suppression prescribed by TMD evolution.Comment: 4 pages, 2 figures. Version published in Physical Review Letter

Forward Jets and Energy Flow in Hadronic Collisions

We observe that at the Large Hadron Collider, using forward + central detectors, it becomes possible for the first time to carry out calorimetric measurements of the transverse energy flow due to "minijets" accompanying production of two jets separated by a large rapidity interval. We present parton-shower calculations of energy flow observables in a high-energy factorized Monte Carlo framework, designed to take into account QCD logarithmic corrections both in the large rapidity interval and in the hard transverse momentum. Considering events with a forward and a central jet, we examine the energy flow in the interjet region and in the region away from the jets. We discuss the role of these observables to analyze multiple parton collision effects.Comment: 9 pages, 5 figures. Version2: added results on azimuthal distributions and more discussion of energy flow definition using jet clusterin

Evidence for Factorization Breaking in Diffractive Low-Q^2 Dijet Production

We calculate diffractive dijet production in deep-inelastic scattering at next-to-leading order of perturbative QCD, including contributions from direct and resolved photons, and compare our predictions to preliminary data from the H1 collaboration at HERA. In contrast to recent experimental claims, evidence for factorization breaking is found only for resolved, and not direct, photon contributions. No evidence is found for large normalization uncertainties in diffractive parton densities. The results confirm theoretical expectations for the (non-)cancellation of soft singularities in diffractive scattering as well as previous results for (almost) real photoproduction.Comment: 4 pages, 3 figure

Color transparency in deeply inelastic diffraction

We suggest a simple physical picture for the diffractive parton distributions that appear in diffractive deeply inelastic scattering. In this picture, partons impinging on the proton can have any transverse separation, but only when the separation is small can they penetrate the proton without breaking it up. By comparing the predictions from this picture with the diffractive data from HERA, we determine rough values for the small separations that dominate the diffraction process.Comment: 10 pages, 2 figures; v2: citations added, two comments revised and expanded, results unchange

TMDlib and TMDplotter: library and plotting tools for transverse-momentum-dependent parton distributions

Transverse-momentum-dependent distributions (TMDs) are central in high-energy physics from both theoretical and phenomenological points of view. In this manual we introduce the library, TMDlib, of fits and parameterisations for transverse-momentum-dependent parton distribution functions (TMD PDFs) and fragmentation functions (TMD FFs) together with an online plotting tool, TMDplotter. We provide a description of the program components and of the different physical frameworks the user can access via the available parameterisations.Comment: version 2, referring to TMDlib 1.0.2 - comments and references adde

QCD

We discuss QCD studies that will be possible at LEP2. We examine both experimental and theoretical aspects of jets, fragmentation functions, multiplicities and particle spectra.Comment: 44 pages, Latex, epsfig, 18 figures, to appear on the Report of the Workshop on Physics at LEP2, CERN 96-01, vol. 1, 199

The CCFM Monte Carlo generator CASCADE 2.2.0

CASCADE is a full hadron level Monte Carlo event generator for ep, \gamma p and p\bar{p} and pp processes, which uses the CCFM evolution equation for the initial state cascade in a backward evolution approach supplemented with off - shell matrix elements for the hard scattering. A detailed program description is given, with emphasis on parameters the user wants to change and variables which completely specify the generated events

Soft Photon Spectrum in Orthopositronium and Vector Quarkonium Decays

QED gauge invariance, when combined with analyticity, leads to constraints on the low energy end of the emitted photon spectra. This is known as Low's theorem. It is shown that the Ore-Powell result, as well as further developments for the orthopositronium differential decay rate, are in contradiction with Low's theorem, i.e. that their predicted soft photon spectra are incorrect. A solution to this problem is presented. The implications for the orthopositronium lifetime puzzle, the charmonium rho-pi puzzle, the prompt photon spectrum in inclusive quarkonium decays and the extraction of alpha_S from quarkonium annihilation rates are briefly commented.Comment: LaTeX, 10 page

Targeted natural killer cell–based adoptive immunotherapy for the treatment of patients with NSCLC after radiochemotherapy: a randomized phase II clinical trial

Purpose: Non–small cell lung cancer (NSCLC) is a fatal disease with poor prognosis. A membrane-bound form of Hsp70 (mHsp70) which is selectively expressed on high-risk tumors serves as a target for mHsp70-targeting natural killer (NK) cells. Patients with advanced mHsp70-positive NSCLC may therefore benefit from a therapeutic intervention involving mHsp70-targeting NK cells. The randomized phase II clinical trial (EudraCT2008-002130-30) explores tolerability and efficacy of ex vivo–activated NK cells in patients with NSCLC after radiochemotherapy (RCT). Patients and Methods: Patients with unresectable, mHsp70-positive NSCLC (stage IIIa/b) received 4 cycles of autologous NK cells activated ex vivo with TKD/IL2 [interventional arm (INT)] after RCT (60–70 Gy, platinum-based chemotherapy) or RCT alone [control arm (CTRL)]. The primary objective was progression-free survival (PFS), and secondary objectives were the assessment of quality of life (QoL, QLQ-LC13), toxicity, and immunobiological responses. Results: The NK-cell therapy after RCT was well tolerated, and no differences in QoL parameters between the two study arms were detected. Estimated 1-year probabilities for PFS were 67% [95% confidence interval (CI), 19%–90%] for the INT arm and 33% (95% CI, 5%–68%) for the CTRL arm (P = 0.36, 1-sided log-rank test). Clinical responses in the INT group were associated with an increase in the prevalence of activated NK cells in their peripheral blood