| Records |
| Author |
Hernandez-Pinto, R.J.; Sborlini, G.F.R.; Rodrigo, G. |
| Title |
Towards gauge theories in four dimensions |
Type |
Journal Article |
| Year |
2016 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
| Volume |
02 |
Issue |
2 |
Pages |
044 - 14pp |
| Keywords |
NLO Computations |
| Abstract |
The abundance of infrared singularities in gauge theories due to unresolved emission of massless particles (soft and collinear) represents the main difficulty in perturbative calculations. They are typically regularized in dimensional regularization, and their subtraction is usually achieved independently for virtual and real corrections. In this paper, we introduce a new method based on the loop-tree duality (LTD) theorem to accomplish the summation over degenerate infrared states directly at the integrand level such that the cancellation of the infrared divergences is achieved simultaneously, and apply it to reference examples as a proof of concept. Ultraviolet divergences, which are the consequence of the point-like nature of the theory, are also reinterpreted physically in this framework. The proposed method opens the intriguing possibility of carrying out purely four-dimensional implementations of higher-order perturbative calculations at next-to-leading order (NLO) and beyond free of soft and final-state collinear subtractions. |
| Address |
[Hernandez-Pinto, Roger J.; Sborlini, German F. R.; Rodrigo, German] Univ Valencia, Inst Fis Corpuscular, Consejo Super Invest Cient, Pare Cient, E-46980 Valencia, Spain, Email: rogerjose.hernandez@ific.uv.es; |
| Corporate Author |
|
Thesis |
|
Publisher  |
Springer |
Place of Publication |
|
Editor |
|
| Language |
English |
Summary Language |
|
Original Title |
|
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1029-8479 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
WOS:000375270700002 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
2661 |
| Permanent link to this record |
| |
|
| |
| Author |
de Florian, D.; Sborlini, G.F.R.; Rodrigo, G. |
| Title |
QED corrections to the Altarelli-Parisi splitting functions |
Type |
Journal Article |
| Year |
2016 |
Publication |
European Physical Journal C |
Abbreviated Journal |
Eur. Phys. J. C |
| Volume |
76 |
Issue |
5 |
Pages |
282 - 6pp |
| Keywords |
|
| Abstract |
We discuss the combined effect of QED and QCD corrections to the evolution of parton distributions. We extend the available knowledge of the Altarelli-Parisi splitting functions to one order higher in QED, and we provide explicit expressions for the splitting kernels up to O(alpha alpha(S)). The results presented in this article allow one to perform a parton distribution function analysis reaching full NLO QCD-QED combined precision. |
| Address |
[de Florian, Daniel] Univ Buenos Aires, FCEyN, Dept Fis, 1428 Pabellon 1 Ciudad Univ, Buenos Aires, Argentina, Email: deflo@unsam.edu.ar; |
| Corporate Author |
|
Thesis |
|
| Publisher |
Springer |
Place of Publication |
|
Editor |
|
| Language |
English |
Summary Language |
|
Original Title |
|
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1434-6044 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
WOS:000376606500002 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
2692 |
| Permanent link to this record |
| |
|
| |
| Author |
Sborlini, G.F.R.; Driencourt-Mangin, F.; Hernandez-Pinto, R.J.; Rodrigo, G. |
| Title |
Four-dimensional unsubtraction from the loop-tree duality |
Type |
Journal Article |
| Year |
2016 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
| Volume |
08 |
Issue |
8 |
Pages |
160 - 42pp |
| Keywords |
NLO Computations |
| Abstract |
We present a new algorithm to construct a purely four dimensional representation of higher-order perturbative corrections to physical cross-sections at next-to-leading order (NLO). The algorithm is based on the loop-tree duality (LTD), and it is implemented by introducing a suitable mapping between the external and loop momenta of the virtual scattering amplitudes, and the external momenta of the real emission corrections. In this way, the sum over degenerate infrared states is performed at integrand level and the cancellation of infrared divergences occurs locally without introducing subtraction counter-terms to deal with soft and final-state collinear singularities. The dual representation of ultraviolet counter-terms is also discussed in detail, in particular for self-energy contributions. The method is first illustrated with the scalar three-point function, before proceeding with the calculation of the physical cross-section for gamma* -> q (q) over bar (g), and its generalisation to multi-leg processes. The extension to next-to-next-to-leading order (NNLO) is briefly commented. |
| Address |
[Sborlini, German F. R.; Driencourt-Mangin, Felix; Hernandez-Pinto, Roger J.; Rodrigo, German] Univ Valencia, Inst Fis Corpuscular, CSIC, Parc Cient, E-46980 Valencia, Spain, Email: gfsborlini@df.uba.ar; |
| Corporate Author |
|
Thesis |
|
| Publisher |
Springer |
Place of Publication |
|
Editor |
|
| Language |
English |
Summary Language |
|
Original Title |
|
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1029-8479 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
WOS:000382685100001 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
2793 |
| Permanent link to this record |
| |
|
| |
| Author |
Sborlini, G.F.R.; Driencourt-Mangin, F.; Rodrigo, G. |
| Title |
Four-dimensional unsubtraction with massive particles |
Type |
Journal Article |
| Year |
2016 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
| Volume |
10 |
Issue |
10 |
Pages |
162 - 34pp |
| Keywords |
NLO Computations |
| Abstract |
We extend the four-dimensional unsubtraction method, which is based on the loop-tree duality (LTD), to deal with processes involving heavy particles. The method allows to perform the summation over degenerate IR configurations directly at integrand level in such a way that NLO corrections can be implemented directly in four space-time dimensions. We define a general momentum mapping between the real and virtual kinematics that accounts properly for the quasi-collinear configurations, and leads to an smooth massless limit. We illustrate the method first with a scalar toy example, and then analyse the case of the decay of a scalar or vector boson into a pair of massive quarks. The results presented in this paper are suitable for the application of the method to any multipartonic process. |
| Address |
[Sborlini, German F. R.; Driencourt-Mangin, Felix; Rodrigo, German] Univ Valencia, CSIC, Inst Fis Corpuscular, Parc Cient, E-46980 Valencia, Spain, Email: german.sborlini@ific.uv.es; |
| Corporate Author |
|
Thesis |
|
| Publisher |
Springer |
Place of Publication |
|
Editor |
|
| Language |
English |
Summary Language |
|
Original Title |
|
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1029-8479 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
WOS:000387374000001 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
no |
| Call Number |
IFIC @ pastor @ |
Serial |
2853 |
| Permanent link to this record |
| |
|
| |
| Author |
de Florian, D.; Sborlini, G.F.R.; Rodrigo, G. |
| Title |
Two-loop QED corrections to the Altarelli-Parisi splitting functions |
Type |
Journal Article |
| Year |
2016 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
| Volume |
10 |
Issue |
10 |
Pages |
056 - 16pp |
| Keywords |
NLO Computations; QCD Phenomenology |
| Abstract |
We compute the two-loop QED corrections to the Altarelli-Parisi (AP) splitting functions by using a deconstructive algorithmic Abelianization of the well-known NLO QCD corrections. We present explicit results for the full set of splitting kernels in a basis that includes the leptonic distribution functions that, starting from this order in the QED coupling, couple to the partonic densities. Finally, we perform a phenomenological analysis of the impact of these corrections in the splitting functions. |
| Address |
[de Florian, Daniel] UNSAM, ICAS, Campus Miguelete,25 Mayo & Francia, RA-1650 Buenos Aires, DF, Argentina, Email: deflo@unsam.edu.ar; |
| Corporate Author |
|
Thesis |
|
| Publisher |
Springer |
Place of Publication |
|
Editor |
|
| Language |
English |
Summary Language |
|
Original Title |
|
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1029-8479 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
WOS:000386669900007 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
2863 |
| Permanent link to this record |
