13,856 research outputs found
On the contribution of twist-3 multi-gluon correlation functions to single transverse-spin asymmetry in SIDIS
We study the single spin asymmetry (SSA) induced by purely gluonic
correlation inside a nucleon, in particular, by the three-gluon correlation
functions in the transversely polarized nucleon, . This
contribution is embodied as a twist-3 mechanism in the collinear factorization
framework and controls the SSA to be observed in the -meson production with
large transverse-momentum in semi-inclusive DIS (SIDIS), . We define the relevant three-gluon correlation functions in
the nucleon, and determine their complete set at the twsit-3 level taking into
account symmetry constraints in QCD. We derive the single-spin-dependent cross
section for the -meson production in SIDIS, taking into account all the
relevant contributions at the twist-3 level. The result is obtained in a
manifestly gauge-invariant form as the factorization formula in terms of the
three-gluon correlation functions and reveals the five independent structures
with respect to the dependence on the azimuthal angle for the produced
meson. We also demonstrate the remarkable relation between the twist-3
single-spin-dependent cross section and twist-2 cross sections for the
-meson production, as a manifestation of universal structure behind the SSA
in a variety of hard processes.Comment: 8 pages, 2 figures. To appear in the proceedings of the 19th
International Spin Physics Symposium (SPIN2010), Juelich, Germany, Sept.27 -
Oct.2, 201
Three-gluon contribution to the single spin asymmetry in Drell-Yan and direct-photon processes
We derive the single-spin-dependent cross section for the Drell-Yan
lepton-pair production and the direct-photon production in the -collision
induced by the twist-3 three-gluon correlation functions in the transversely
polarized nucleon in the leading order with respect to the QCD coupling
constant. Combined with the contribution from the twist-3 quark-gluon
correlation functions in the literature, this completes the twist-3 cross
section for these processes. We also present a model calculation of the
asymmetry for the direct photon production at the RHIC energy, demonstrating
the sensitivity of the asymmetry to the form of the three-gluon correlation
functions. In particular, we show that the asymmetry in the backward direction
of the polarized nucleon is determined by the small- behavior of the
correlation functions.Comment: 15 pages, 3 figure
PDE for : a rough volatility context
Recent mathematical advances in the context of rough volatility have
highlighted interesting and intricate connections between path-dependent
partial differential equations and backward stochastic partial differential
equations. In this note, we make this link precise, identifying the slightly
obscure random field introduced in [Pricing options under rough volatility with
backward SPDEs, C. Bayer; J. Qiu and Y. Yao. SIFIN, 13(1), 179-212 (2022)] as a
pathwise derivative of the value function
New phenomena in interaction of intense ultrashort light pulses with transparent materials: from 3D self-assembled nanostructures to quill writing and nonreciprocal photosensitivity
Interaction of intense ulrashort light pulses with transparent materials reveal new ultrafast phenomena. Recent demonstrations of 3D nanoripple formation, ultrafast laser calligraphy and nonreciprocal photosensitivity are reviewed
Probing the twist-3 multi-gluon correlation functions by pp \to DX
We study the single spin asymmetry (SSA) for the D-meson production
in the collision, , in the framework of the collinear
factorization. Since the charm quark is mainly produced through the
-pair creation from the gluon-fusion process, this is an ideal
process to probe the twist-3 triple-gluon correlation functions in the
polarized nucleon. We derive the corresponding cross section formula for the
contribution of the triple-gluon correlation function to in , applying the method developed for in our
previous study. As in the case of , our result differs from
a previous study in the literature. We will also present a simple estimate of
the triple-gluon correlation functions based on the preliminary data on
by RHIC.Comment: to appear in the proceedings of the 19th International Spin Physics
Symposium (Spin2010), Sept.27 - Oct.2, 2010, Juelich, Germany, 5 pages, 2
figure
A proof of the Gordon Conjecture
A combinatorial proof of the Gordon Conjecture: The sum of two Heegaard
splittings is stabilized if and only if one of the two summands is stabilized.Comment: 23 pages, 17 figures. Revised version incorporates Ruifeng Qiu as
coautho
Chiral-Odd Contribution to Single-Transverse Spin Asymmetry in Hadronic Pion Production
A formula for the single transverse spin asymmetry in the large- pion
production in the nucleon-nucleon collision is derived. We focuss on the
chiral-odd contribution where the transversity distribution and the chiral-odd
spin-independent twist-3 distribution contributes. This contribution is
expected to give rise to a large effect at .Comment: Latex file 10 pages + 2 figures attached as PS and EPS files. A minor
correction is include
Commentary: A novel and effective ECG method to differentiate right from left ventricular outflow tract arrhythmias: Angle-corrected V2S
This commentary builds on the recently published original paper of Qiu et al. (1). The most common origin of premature ventricular complexes and ventricular tachycardias of patients in the absence of structural heart disease is the right and left ventricular outflow tracts (RVOT/LVOT). Catheter ablation (CA) has been an effective method for outflow tract ventricular arrhythmias (OTVAs) (2). It is necessary to predict the origin of OTVAs before CA for choosing the procedural strategy, reducing complications, and saving the operation time (3, 4). Qiu et al. presented a novel electrocardiogram (ECG) algorithm, âcardiac rotation-correctedâ angle-corrected V2S (hereafter, V2S angle), to differentiate the LVOT origin from the RVOT origin with higher predictive accuracy (1). . .
Revealing extraordinary properties of femtosecond laser writing in glass
Modification of transparent materials with ultrafast lasers has attracted considerable interest due to a wide range of applications including laser surgery, integrated optics, optical data storage, 3D micro- and nano-structuring [1].Three different types of material modifications can be induced with ultrafast laser irradiation in the bulk of a transparent material, silica glass in particular: an isotropic refractive index change (type 1); a form birefringence associated with self-assembled nanogratings and negative refractive index change (type 2) [2,3]; and a void (type 3). In fused silica the transition from type 1 to type 2 and finally to type 3 modification is observed with an increase of fluence. Recently, a remarkable phenomenon in ultrafast laser processing of transparent materials has been reported manifesting itself as a change in material modification by reversing the writing direction [4]. The phenomenon has been interpreted in terms of anisotropic plasma heating by a tilted front of the ultrashort laser pulse. Moreover a change in structural modification has been demonstrated in glass by controlling the direction of pulse front tilt, achieving a calligraphic style of laser writing which is similar in appearance to that inked with the bygone quill pen [5]. It has also been a common belief that in a homogeneous medium, the photosensitivity and corresponding light-induced material modifications do not change on the reversal of light propagation direction. More recently it have observed that in a noncentrosymmetric medium, modification of the material can be different when light propagates in opposite directions (KaYaSo effect) [6]. Non-reciprocity is produced by magnetic field (Faraday effect) and movement of the medium with respect to the direction of light propagation: parallel (Sagnac effect) or perpendicular (KaYaSo effect). Moreover a new phenomenon of ultrafast light blade, representing itself the first evidence of anisotropic sensitivity of isotropic medium to femtosecond laser radiation has been recently discovered [7]. We attribute these new phenomena to the anisotropy of the light-matter interaction caused by space-time couplings in ultrashort light pulses. This intrinsic spatio-temporal asymmetry of light opens an interesting opportunity in the control of photon flux interacting with a target submerged into condensed isotropic medium. We anticipate that the observed phenomena will open new opportunities in laser material processing, laser surgery, optical manipulation and data storage
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