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Measurements of quarkonium production in p-Pb and Pb-Pb collisions with ALICE at the LHC
Get PDFALICE (A Large Ion Collider Experiment) is devoted to the study of heavy-ion collisions at LHC energies. In such collisions, a deconfined state of hadronic matter, the Quark-Gluon Plasma (QGP), is formed. Quarkonium states
are important probes to study the QGP evolution since their formation happens early during the collision and their production rate is modified in the interaction with the medium. The latest ALICE results on quarkonium production in Pb-Pb and p-Pb collisions will be presented and discussed
LHCb heavy-ion results in collider and fixed-target mode
Get PDFLHCb is a fully instrumented forward spectrometer at the LHC with a pseudorapidity coverage 2 <η< 5 designed for the study of hadrons containing b and c-quarks in pp collisions. The forward acceptance and its instrumentation
for high-precision vertex reconstruction, tracking and particle identification allow for unique studies in heavy-ion collisions. Furthermore, a system for noble gas
injections into the beam vacuum at the nominal interaction point can be used for fixed target studies with the LHC beams. With these data sets, it is possible to constrain nuclear modification of heavy-flavour and quarkonium production with high precision in proton-induced reactions. This is of particular interest as a baseline for deconfinement signature studies in ion-ion collisions. Furthermore, in the collider mode, the production of the charm and beauty quarks probe low Bjorken-x values in the initial state of the ions where gluon saturation may start to play a role. The fixed-target data cover a kinematic range which is particular interesting for the search of intrinsic charm at high Bjorken-x. Recent results on heavy-flavour and quarkonium production in proton-lead collisions in collider mode as well as in proton-Helium and proton-Argon collisions are presented
In-beam γ-ray spectroscopy of nuclei in the 132Sn region performed at RIKEN
Get PDFThe nucleus 133Sn83, with one single neutron outside doubly-magic 132Sn, was studied at the Radioactive Isotope Beam Factory at RIKEN. The excited states of 133Sn were populated via one-neutron knockout from a 134Sn beam on a
carbon target at relativistic energies. Besides the γ rays emitted following the decay of known neutron single-particle states, additional γ strength above the neutron
separation energy was observed for the first time. It has been interpreted as evidence for a competition between γ-ray and neutron emission in the decay of neutronunbound states in 133Sn
Statistical approach for the first extraction of dipole dynamical polarizabilities from proton real Compton scattering data
Get PDFIn this work we describe a statistical technique that has been recently applied for the extraction of the proton scalar dipole dynamical polarizabilities from real Compton scattering data. The technique is based on the simplex minimization and on the parametric bootstrap and has several important advantages with respect to the standard χ2 minimization technique, as, for example, the possibility to include in a straightforward way the systematic error in the minimization procedure
Underground measurement of proton-induced reactions on 6Li at LUNA
Get PDFA discrepancy exists between the 6Li abundances predicted from big bang nucleosynthesis models and those measured in pre-main sequence stars. To further constrain the predicted abundances of 6Li in these stars, high accuracy
measurements are required of reactions destroying 6Li, namely 6Li(p,γ) 7Be and 6Li(p,α) 3He. Their reaction cross-sections were recently measured at astrophysically relevant energies at the Laboratory for Underground Nuclear Astrophysics (LUNA). I present both the experimental setup and current status of the data analysis
Low-energy cross section measurements of the 22Ne(p, γ)23Na reaction
Get PDFBecause of a large number of uncertain resonances in the Gamow window, the 22Ne(p, γ) 23Na reaction rate was the most uncertain in the NeNa cycle. Recently, a new direct study of the 22Ne(p, γ) 23Na reaction has been performed
at the Laboratory for Underground Nuclear Astrophysics (LUNA). A windowless gas target and two complementary setups have been used, to obtain both high resolution and high efficiency measurements. The new resonances at 156.2, 189.5 and 259.7 keV have been discovered and their decay scheme has been determined. The tentative resonances at 71 and 105 keV have not been observed and improved upper limits have been put on their strength. Moreover, the high-efficiency setup allowed the measurement of the non-resonant cross section at unprecedentedly low energies. The thermonuclear reaction rate based on the new measurements has been evaluated
Recent THM investigations of the 7Be(n,α)4He reaction in the BBN scenario
Get PDF7Be-n induced reactions play a key role in the final lithium abundances as produced during the Big Bang Nucleosynthesis (BBN). This has triggered a lot of works in the last years in which various experimental approaches have been followed. Here the recent investigation performed via the Trojan Horse Method (THM) will be discussed and its impact evaluated
The AEgIS experiment at CERN: Probing antimatter gravity
Get PDFThe AE¯gIS experiment at CERN’s Antiproton Decelerator is set up to precisely measure the gravitational interaction between matter and antimatter. For this purpose, antihydrogen will be formed from cold antiprotons and positronium, the hydrogen-like bound state of an electron and a positron. Subsequently,
the free-fall acceleration of a cold horizontal beam of antihydrogen will be measured by a deflectometer. The present status, recent experimental progress and the medium-term plan of the AE¯gIS experiment are presented
Towards the W-boson mass measurement with the CMS experiment
Get PDFThe mass of the W-boson, mW , is a fundamental parameter of the Standard Model of particle physics. Its value is correlated with other observables of the theory and any deviation from the expectation would provide a striking hint of the possible existence of new physics. The measurement of mW represents an outstanding experimental challenge, requiring a deep understanding of both the
detector and the theoretical uncertainties. In a proton-proton collider, such as the LHC, the uncertainty is dominated by the parton distribution functions (PDFs). This paper describes the potential and prospects of an ancillary measurement that is being carried out by the CMS Collaboration to constrain the PDF uncertainty on mW , namely the W-boson rapidity distribution as a function of its helicity state
HOLMES, an experiment for a direct measurement of neutrino mass
Get PDFThe neutrino mass is a fundamental parameter of the Standard Model and the measurement of its value is one of the most compelling issues in particle physics. HOLMES is an experiment set up at the University of Milano-Bicocca
aiming at performing a direct measurement of the neutrino mass from the Electron Capture (EC) decay of 163Ho. HOLMES will use low-temperature calorimeters, avoiding the typical systematics of spectrometers arising from the use of any external source, in order to precisely measure the energy of the electrons emitted in the EC decay. In this contribution we outline the steps which will lead to the HOLMES measurement of the neutrino mass