7,611 research outputs found
QCD Factorization for heavy quarkonium production at collider energies
In this talk, I briefly review several models of the heavy quarkonium
production at collider energies, and discuss the status of QCD factorization
for these production models.Comment: 7 pages, 12 figures, Talk presented at the Conference on Quark
Confinement and Hadron Spectrum VII, Ponta Delgada, Portugal, 2-7 September,
200
Knot Weight Systems from Graded Symplectic Geometry
We show that from an even degree symplectic NQ-manifold, whose homological
vector field Q preserves the symplectic form, one can construct a weight system
for tri-valent graphs with values in the Q-cohomology ring, satisfying the IHX
relation. Likewise, given a representation of the homological vector field, one
can construct a weight system for the chord diagrams, satisfying the IHX and
STU relations. Moreover we show that the use of the 'Gronthendieck connection'
in the construction is essential in making the weight system dependent only on
the choice of the NQ-manifold and its representation.Comment: 26 pages, revised versio
Introduction to Graded Geometry, Batalin-Vilkovisky Formalism and their Applications
These notes are intended to provide a self-contained introduction to the
basic ideas of finite dimensional Batalin-Vilkovisky (BV) formalism and its
applications. A brief exposition of super- and graded geometries is also given.
The BV-formalism is introduced through an odd Fourier transform and the
algebraic aspects of integration theory are stressed. As a main application we
consider the perturbation theory for certain finite dimensional integrals
within BV-formalism. As an illustration we present a proof of the isomorphism
between the graph complex and the Chevalley-Eilenberg complex of formal
Hamiltonian vectors fields. We briefly discuss how these ideas can be extended
to the infinite dimensional setting. These notes should be accessible to both
physicists and mathematicians.Comment: 67 pages, typos corrected, published versio
5D Super Yang-Mills on Sasaki-Einstein manifolds
On any simply connected Sasaki-Einstein five dimensional manifold one can
construct a super Yang-Mills theory which preserves at least two
supersymmetries. We study the special case of toric Sasaki-Einstein manifolds
known as manifolds. We use the localisation technique to compute the
full perturbative part of the partition function. The full equivariant result
is expressed in terms of certain special function which appears to be a curious
generalisation of the triple sine function. As an application of our general
result we study the large behaviour for the case of single hypermultiplet
in adjoint representation and we derive the -behaviour in this case.Comment: 43 pages, typos and mistakes correcte
Knot Invariants and New Weight Systems from General 3D TFTs
We introduce and study the Wilson loops in a general 3D topological field
theories (TFTs), and show that the expectation value of Wilson loops also gives
knot invariants as in Chern-Simons theory. We study the TFTs within the
Batalin-Vilkovisky (BV) and Alexandrov-Kontsevich-Schwarz-Zaboronsky (AKSZ)
framework, and the Ward identities of these theories imply that the expectation
value of the Wilson loop is a pairing of two dual constructions of (co)cycles
of certain extended graph complex (extended from Kontsevich's graph complex to
accommodate the Wilson loop). We also prove that there is an isomorphism
between the same complex and certain extended Chevalley-Eilenberg complex of
Hamiltonian vector fields. This isomorphism allows us to generalize the Lie
algebra weight system for knots to weight systems associated with any
homological vector field and its representations. As an example we construct
knot invariants using holomorphic vector bundle over hyperKahler manifolds.Comment: 55 pages, typos correcte
Collinear factorization for deep inelastic scattering structure functions at large Bjorken xB
We examine the uncertainty of perturbative QCD factorization for hadron
structure functions in deep inelastic scattering at a large value of the
Bjorken variable xB. We analyze the target mass correction to the structure
functions by using the collinear factorization approach in the momentum space.
We express the long distance physics of structure functions and the leading
target mass corrections in terms of parton distribution functions with the
standard operator definition. We compare our result with existing work on the
target mass correction. We also discuss the impact of a final-state jet
function on the extraction of parton distributions at large fractional momentum
x.Comment: 18 pages, 10 figures; discussion on baryon number conservation
clarifie
Heavy quarkonium production in hadronic collisions in TMD framework
Heavy quarkonium () production at low transverse momentum
() in high-energy hadronic collisions is revisited from the point of
view of transverse momentum dependent (TMD) framework. We perform resummation
of double logarithmic correction associated with initial-state soft gluon
shower for production by employing Collins-Soper-Sterman (CSS)
formalism. We show that the CSS formalism provides a nice description of
production data in p+ collisions at Tevatron and p+p
collisions at the LHC.Comment: 6 pages, 2 figures, proceedings of QCD Evolution 2017, 22-26 May
2017, Newport News, VA-US
Novel Phenomenology of Parton Distributions from the Drell-Yan Process
The Drell-Yan massive lepton-pair production in hadronic collisions provides
a unique tool complementary to the Deep-Inelastic Scattering for probing the
partonic substructures in hadrons. We review key concepts, approximations, and
progress for QCD factorization of the Drell-Yan process in terms of collinear
or transverse momentum dependent (TMD) parton distribution functions. We
present experimental results from recent fixed-target Drell-Yan as well as
and boson production at colliders, focussing on the topics of flavor
structure of the nucleon sea as well as the extraction of novel Sivers and
Boer-Mulders functions via single transverse spin asymmetries and azimuthal
lepton angular distribution of the Drell-Yan process. Prospects for future
Drell-Yan experiments are also presented.Comment: 50 pages and 23 figures, and references added and minor typos
correcte
Wilson Lines from Representations of NQ-Manifolds
An NQ-manifold is a non-negatively graded supermanifold with a degree 1
homological vector field. The focus of this paper is to define the Wilson
loops/lines in the context of NQ-manifolds and to study their properties. The
Wilson loops/lines, which give the holonomy or parallel transport, are familiar
objects in usual differential geometry, we analyze the subtleties in the
generalization to the NQ-setting and we also sketch some possible applications
of our construction.Comment: 37 page
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