Archivi tag: Nuclear Physics

Origin of Matter and Evolution of Galaxies

The 13th international symposium on Origin of Matter and Evolution of Galaxies (OMEG2015) will be held in Beijing, China on June 24-27, 2015. This symposium is the 13th of such series, started 1988, to exchange the progress of nuclear astrophysics and related fields. As demonstrated in previous ones, this symposium series provide good opportunity to attract researchers in fields of nuclear physics, astrophysics, and more. Continua a leggere Origin of Matter and Evolution of Galaxies

The XXII International Workshop on High Energy Physics and Quantum Field Theory

The Workshop continues a series of workshops started by the Skobeltsyn Institute of Nuclear Physics of Lomonosov Moscow State University (SINP MSU) in 1985 and conceived with the purpose of presenting topics of current interest and providing a stimulating environment for scientific discussion on new developments in theoretical and experimental high energy physics and physical programs for future colliders. Continua a leggere The XXII International Workshop on High Energy Physics and Quantum Field Theory

13° Nordic Meeting on Nuclear Physics

The 13th Nordic Meeting on Nuclear Physics will be held from 13th -17th April 2015 in Saariselkä in Finnish Lapland. The meeting is the latest in the series of conferences which have been held every few years since the 1970’s with the location rotating between Denmark, Finland, Norway and Sweden. The 12th Nordic Meeting was organized in Stockholm in June  2011. Continua a leggere 13° Nordic Meeting on Nuclear Physics

Quarks and Nuclear Physics

QNP2015 is the Seventh International Conference devoted to Quarks and Nuclear Physics. It is anticipated that QCD practitioners, both experimentalists and theorists, will gather at the Universidad Técnica Federico Santa María, in Valparaíso, Chile during the week of March 2, 2015 to present and discuss the latest advances in the field. Continua a leggere Quarks and Nuclear Physics

Heavy quarks as ideal probes for quark-gluon plasma studies

Subito dopo il Big Bang, lo spazio era caratterizzato da una sorta di “zuppa primordiale” composta di quark e gluoni, ossia particelle di materia e di interazioni fondamentali. Questo plasma super denso si raffreddò quasi istantaneamente e la sua, seppure breve, esistenza contribuì sostanzialmente a creare le condizioni iniziali da cui si è successivamente evoluto il nostro Universo. Ma per capire meglio queste fasi iniziali della storia cosmica, gli scienziati devono ricreare nei grandi acceleratori di particelle quel plasma primordiale: è il caso del Relativistic Heavy Ion Collider (RHIC) presso il Brookhaven National Laboratory (BNL) dove si stanno analizzando i dati degli ultimi anni grazie ad un esperimento noto come STAR (Solenoidal Tracker at RHIC). A tale complesso è stato aggiunto di recente un nuovo rivelatore, denominato Heavy Flavor Tracker, il più avanzato nel suo genere e che servirà per studiare i processi di decadimento degli adroni costituiti da quark charm e bottom.

Scientists and engineers at the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab), have played a major role in the development of the STAR Heavy Flavor Tracker. The STAR HFT is actually the collective name for three separate silicon-based detector systems that make it possible for the first time to directly track the decay products of hadrons comprised of flavors (types) of quarks, “charm” and “bottom,” with heavy mass. Heavy quarks are considered ideal probes for quark-gluon plasma studies; however, their low production yield and short life-span (a fraction of a microsecond) make them difficult to study in heavy ion collisions that also produce huge quantities of light flavor particles. The HFT was first conceived nearly 15 years ago by Berkeley Lab’s Howard Wieman, a physicist with the Lab’s Nuclear Sciences Division who also played a prominent role in the creation of STAR. The HFT construction project, which began a few years later, was initially led at Berkeley Lab by Hans Georg Ritter, a physicist who served as head of the Nuclear Science Division’s Relativistic Nuclear Collisions program (RNC) for many years. “The HFT enables precision tracking measurements of heavy quarks at low momentum where the particle production is most sensitive to the bulk medium created in heavy ion collisions”, says Nu Xu, a physicist also with Berkeley Lab’s Nuclear Science Division who is the current spokesperson for the STAR experiment. “This allows us to distinguish the decay vertices of heavy flavor particles from primary vertices and significantly reduces combinational background, which yields cleaner measurements with a higher level of significance”. The importance of the HFT’s precision measurements at low momentum to quark-gluon plasma studies is explained by Peter Jacobs, a Berkeley Lab physicist who now heads the Nuclear Science Division’s RNC program. “Theorists claim they can calculate the dynamical behavior of heavy quarks in matter more accurately than that of light quarks or gluons. Some even think they can calculate the dynamical behavior of heavy quarks in the quark-gluon plasma using models inspired by string theory”, Jacobs says. “One of the things we will be testing with the HFT is the different predictions of the behavior of heavy flavors in the quark-gluon plasma made by string-inspired models versus more conventional physics”.

Berkeley Lab scientists and engineers are now developing a new, larger version of the HFT which they propose to be fabricated for the ALICE detector at CERN’s Large Hadron Collider. “If approved, this will be an upgrade to the Inner Tracking System of the ALICE experiment at the LHC that is a direct follow-on to the STAR HFT, utilizing a number of HFT developments”, says Jacobs. “It is proposed to be installed during the next long LHC shutdown in 2018 and will essentially be a 25 giga-pixel camera made up of 11 square meters of silicon, about 30 times larger than the HFT at STAR”.

LBL: Heavy Flavor Tracker for STAR

arXiv: Heavy Flavor Tracker (HFT) : A new inner tracking device at STAR

Neutron Stars: Nuclear Physics, Gravitational Waves and Astronomy

A basic cornerstone of modern physics is the quest to describe quantitatively the properties of nuclear matter. Neutron stars are unique beacons in this journey, as their interiors expose matter to extreme regimes of density, temperature and energy, not accessible to terrestrial experiments. Moreover, the intense gravitational fields in these astrophysical compact objects, particularly in binaries, could give rise to potentially detectable signals in the next generation of gravitational wave detectors. The astronomical observation of compact objects thus provides a unique insight into the properties of nuclear matter in extreme regimes. Better and more reliable theoretical tools and a more thorough modeling are required to interpret observations. Finally, one needs to connect present and future observation to the underlying microphysics associated to the strong interaction.

This international workshop aims at bringing together a number of historically disjoint research communities: nuclear physicists, astrophysicists and general relativists. Taking advantage of a multi-disciplinary environment, we plan to identify key issues in compact star physics and to develop strategies to make the most of the new generation of astronomical observatories, gravitational wave detectors and nuclear experiments.