Interplay of QCD, Cosmology and Astroparticle Physics
A special issue of Universe (ISSN 2218-1997).
Deadline for manuscript submissions: closed (31 March 2019) | Viewed by 9346
Special Issue Editor
Special Issue Information
Dear Colleagues,
Quantum Chromodynamics (QCD) encodes a large richness of physical phenomena, and is intensively studied theoretically and experimentally. However, in spite of its success, some of its aspects are not yet fully understood; there remain open questions that demand answers. Most of these questions have important implications in cosmology and astroparticle physics.
The QCD Lagrangian contains ingredients that can clarify key questions concerning cosmology. The term, which breaks conformal symmetry, even in the massless case, is related to the axion field and its search concerns the nature of dark matter and also could contribute to the cosmological constant. Other possibilities of dark matter have been speculated, such as the existence of exotic hadrons made of color-octet complexes. The mentioned term, which is not CP invariant, plays an important role in the equation of the state of the deconfinement transition from hadronic matter to quark gluon matter, such as what happened in the first moments of the Universe after the Big Bang. This term is proportional to the trace anomaly, which measures the departure from a free quark-gluon gas of the obtained strongly-coupled quark gluon matter, and is also related to vacuum structure.
The experiments of the Relativistic Heavy Ion Collider (RHIC) and the Large Hadron Collider (LHC) have created strongly-coupled quark gluon matter in nucleus–nucleus collisions. Most of the observed collective effects have also been seen in pp collisions. In this case, it is not clear how hydrodynamic models can be applied. There is not a unified picture of the transverse momentum distribution of pp data, as well as its azimuthal distribution. The interplay between soft and hard collisions can show interesting relationships between parton entanglement and thermalization. On the other hand, the forward LHC detectors provide important information on elastic and diffractive scattering, which play important roles in determining the hadronic cascade produced in ultrarelativistic cosmic rays. Usual hadronic models, previously-matched to LHC data, are not able to describe some of the cosmic ray data at higher energies, such as the excess of muons and the energy dependence of the distribution of the length of maximum depth. Phenomena like gluon saturation, color reconnection, string interactions, percolation, and string junction working at LHC energies could have implications in the hadronic cascade.
The QCD conformal breaking term, the axion field and the relation to dark matter and the cosmological constant, the strong CP problem, the dependence on the temperature of the trace anomaly, the equation of state close to the deconfinement phase transition, the collective effects produced in colliding small systems and its thermalization, the transverse momentum distributions, including azimuthal distributions and the interplay between soft and hard interactions, the elastic and diffractive scatterings and in general forward physics at LHC and ultrahigh cosmic ray energies, models of hadronic cascade are the subject of special interest at an interplay of QCD with two related fields: Cosmology and Astroparticle Physics.
Prof. Dr. Carlos Pajares
Guest Editor
Manuscript Submission Information
Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.
Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Universe is an international peer-reviewed open access monthly journal published by MDPI.
Please visit the Instructions for Authors page before submitting a manuscript. Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.
Keywords
- conformal symmetry breaking
- axion field
- dark matter
- cosmological constant
- trace anomaly
- equation of state
- deconfinement phase transition
- collectivity in small systems
- thermalization
- interplay between soft and hard interactions
- gluon saturation
- string interactions
- forward LHC Physics
- elastic and diffraction scattering
- proton profile
- ultrahigh cosmic ray energy
- hadronic cascade models
Benefits of Publishing in a Special Issue
- Ease of navigation: Grouping papers by topic helps scholars navigate broad scope journals more efficiently.
- Greater discoverability: Special Issues support the reach and impact of scientific research. Articles in Special Issues are more discoverable and cited more frequently.
- Expansion of research network: Special Issues facilitate connections among authors, fostering scientific collaborations.
- External promotion: Articles in Special Issues are often promoted through the journal's social media, increasing their visibility.
- e-Book format: Special Issues with more than 10 articles can be published as dedicated e-books, ensuring wide and rapid dissemination.
Further information on MDPI's Special Issue polices can be found here.
