Search results for "VARK"

Quark Structure of the X (4500), X (4700) and χc(4P,5P) States

2021

We study some of the main properties (masses and open-flavor strong decay widths) of 4P and 5P charmonia. While there are two candidates for the χc0(4P,5P) states, the X(4500) and X(4700), the properties of the other members of the χc(4P,5P) multiplets are still completely unknown. With this in mind, we start to explore the charmonium interpretation for these mesons. Our second goal is to investigate if the apparent mismatch between the Quark Model (QM) predictions for χc0(4P,5P) states and the properties of the X(4500) and X(4700) mesons can be overcome by introducing threshold corrections in the QM formalism. According to our coupled-channel model results for the threshold mass shifts, th…

Parton distribution functions of heavy mesons on the light front

2019

The parton distribution functions (PDFs) of heavy mesons are evaluated from their light-front wave functions, which are obtained from a basis light-front quantization in the leading Fock sector representation. We consider the mass eigenstates from an effective Hamiltonian consisting of the confining potential adopted from light-front holography in the transverse direction, a longitudinal confinement, and a one-gluon exchange interaction with running coupling. We present the gluon and the sea quark PDFs which we generate dynamically from the QCD evolution of the valence quark distributions.

Ultrarelativistic quark-nucleus scattering in a light-front Hamiltonian approach

2020

We investigate the scattering of a quark on a heavy nucleus at high energies using the time-dependent basis light-front quantization (tBLFQ) formalism, which is the first application of the tBLFQ formalism in QCD. We present the real-time evolution of the quark wave function in a strong classical color field of the relativistic nucleus, described as the color glass condensate. The quark and the nucleus color field are simulated in the QCD SU(3) color space. We calculate the total and the differential cross sections, and the quark distribution in coordinate and color spaces using the tBLFQ approach. We recover the eikonal cross sections in the eikonal limit. We find that the differential cro…

Massive quarks in NLO dipole factorization for DIS : Longitudinal photon

2021

In this work, we will present the first complete calculation of the one-loop longitudinal photon-to-quark-antiquark light cone wave function, with massive quarks. The quark masses are renormalized in the pole mass scheme. The result is used to calculate the next-to-leading order correction to the high energy Deep Inelastic Scattering longitudinal structure function on a dense target in the dipole factorization framework. For massless quarks the next-to-leading order correction was already known to be sizeable, and our result makes it possible to evaluate it also for massive quarks.

Spectrum of fully-heavy tetraquarks from a diquark+antidiquark perspective

2019

Using a relativized diquark model Hamiltonian, we calculate the masses of $J^{PC}=0^{++}$ ground-state tetraquarks in the following systems: $b s \bar b \bar s$, $bb \bar n \bar n$ ($n=u, d$), $bb \bar s \bar s$, $cc\bar c \bar c$, $b b \bar b \bar b$, $b c\bar b \bar c$ and $b b \bar c \bar c$. We also compute extensive spectra for the fully-heavy quark flavour combinations. Finally, as a test of the diquark model approach, we compute the masses of fully-heavy baryons in the diquark model. Our results may be compared soon to the forthcoming experimental data for fully-heavy three-quark systems.

"Waiting for Godot?" : Lithuania and the European Security Order in the 21-century

2000

Lietuvos užsienio ir saugumo politikos principai, kryptys ir pagrindiniai tikslai liko iš esmės nepakitę nuo pat valstybingumo atkūrimo, tačiau politinių sprendimų priėmimo kontekstas per tą laiką gerokai pasikeitė ir keičiasi toliau. Vidurio ir Rytų Europoje žlugus komunistiniams režimams, Šaltojo karo tvarka žlugo neįtikėtinai greitai. 2000 m. aiškėja, kad strateginė aplinka ir mūsų saugumo suvokimas taip pat pakito. Nors Vidurio ir Rytų Europos lyderiai nepamiršta sovietinės praeities, pastarieji dešimt metų leidžia tikėtis, kad šioms valstybėms pavyks sėkmingai integruotis į Vakarų Europos struktūras. 1999 m. Kosovo kampanija privertė peržiūrėti tarptautinio saugumo sampratą, Europos Są…

Varkaus yhteiskunnallisten murrosten näyttämönä 1900-luvun alusta nykypäivään

2020

Tässä kymmenestä artikkelista koostuvassa kokoomateoksessa tarkastellaan Varkautta rakennemuutoksen kanssa kamppailevana pienenä kaupunkina historiallisia dokumentteja sekä vuosina 2016–2017 kerättyjä kysely- ja haastatteluaineistoa hyödyntäen. Pitkän teollisuushistorian omaava Varkauden kaupunki on tämän vuosituhannen ensimmäisinä vuosikymmeninä menettänyt suuren osan teollisista työpaikoistaan ja sen väestö on supistunut voimakkaasti. Kuitenkin koko aikuisväestöä edustava kysely kertoo, että varkautelaiset ovat tyypillisesti tyytyväisiä työhönsä, sosiaalisiin suhteisiinsa ja elämäänsä muutenkin. Varkaus nähdään turvallisena ja hyvän elämän puitteet tarjoavana asuinpaikkana. Hyvinvoinnin t…

Elastiset törmäykset suurienergiaisten partonien poikittaisliikemäärän vaimenemismekanismina kvarkkigluoniplasmassa

2007

Tiheä kvarkkiaine ja Nambu-Jona-Lasinio-malli

2007

Single electron yields from semileptonic charm and bottom hadron decays in Au+Au collisions at √sNN = 200 GeV

2016

The PHENIX Collaboration at the Relativistic Heavy Ion Collider has measured open heavy flavor production in minimum bias Au + Au collisions at √sNN = 200 GeV via the yields of electrons from semileptonic decays of charm and bottom hadrons. Previous heavy flavor electron measurements indicated substantial modification in the momentum distribution of the parent heavy quarks owing to the quark-gluon plasma created in these collisions. For the first time, using the PHENIX silicon vertex detector to measure precision displaced tracking, the relative contributions from charm and bottom hadrons to these electrons as a function of transverse momentum are measured in Au + Au collisions. We compare …