23-27 February 2016
Saha Institute of Nuclear Physics
Asia/Calcutta timezone

Scientific Programme

I) Topic: Precision EW physics at hadron colliders 

Speaker: Alessandro Vicini (Universita' degli Studi di Milano)

Formulation of an event generator that matches a Parton Shower description of radiation to all orders with fixed order exact matrix elements.

Lectures:

1. Precision tests of the Standard Model. Accurate prediction of the W boson mass.

2. NLO results. Renormalization. Soft and collinear divergences.

3. Radiation in the soft/collinear limit. All orders results. The Sudakov form factor.

4. Matching fixed-order and all-order results. The POWHEG approach. Comments on other formulations.

5. Simultaneous matching of QCD and EW results. Prospects towards NNLO accuracy (comments on the already available QCD generators)

Tutorials:

1. To introduce the technique of differential equations to evaluate loop integrals

2. To apply it to the evaluation of simple 1-loop integrals already well known in the literature

3. To consider the possibility of 1-loop integrals expanded at higher orders in D-4, in presence of masses, as the interesting mathematical quantity necessary to perform 2-loop QCDxEW calculations

II) Topic:NNLO QCD calculations in hadronic collisions: the qT subtraction formalism 

Speaker: Giancarlo Ferrera (Universita' degli Studi di Milano)

Lectures:

1. Introduction, the perturbative approach in QCD. Next-to-leading order (NLO) QCD calculations:soft and collinear infrared singularities, factorization theorem of collinear singularities. Jet cross sections: infrared-safe, collinear-safe and collinear-factorizable observables.

2. Factorization of QCD amplitudes in the soft limit (eikonal approximation) and in the collinear limit (Altarelli-Parisi splitting functions). The dipole formalism.

3. Transverse-momentum (qT ) distribution for colourless high-mass systems. Origin of double logarithmic terms in the small qT region. All order Sudakov resummation, dynamics and kinematics factorization, exponentiation. Universality in qT resummation, the Sudakov form factor and the hard-collinear coefficients.

4. The qT subtraction formalism at next-to-next-to-leading order (NNLO): production of colourless high-mass systems. The qT subtraction for coloured final state: the case of top quark anti top pair production.

5. Other approaches and future developments for NNLO QCD calculations (and beyond). Phenomeno-logical comparison of NLO and NNLO QCD predictions with LHC results.

Tutorials:

1. Algorithm for NLO calculations: slicing methods and subtraction methods.

2. NLO calculation of a generic (infrared and collinear safe) observable with no hadrons in the initial state within the dipole formalism.

3. Transverse-momentum resummation for Higgs and Drell-Yan pair production.

4. Numerical implementation of the qT subtraction formalism. The HNNLO and DYNNLO parton level Monte Carlo generators.

 

References

 

III) Topic: Pseudo scalar production at three loop level in QCD at the LHC.

Speaker: MC Kumar (IIT Guwahati)

IV) Topic: Generalized Unitarity to set up Feynman Master Integrals

Speaker: Anurag Tripati (IIT Hyderabad)