Multiplicity dependence of inclusive J/psi production at midrapidity in pp collisions at root s=13 TeV

Measurements of the inclusive J/psi yield as a function of charged-particle pseudorapidity density dN(ch)/d eta in pp collisions at root s = 13 TeV with ALICE at the LHC are reported. The J/psi meson yield is measured at midrapidity (vertical bar y vertical bar <0.9) in the dielectron channel, for events selected based on the charged-particle multiplicity at midrapidity (vertical bar eta vertical bar <1) and at forward rapidity (-3.7 <eta <-1.7 and 2.8 <eta <5.1); both observables are normalized to their corresponding averages in minimum bias events. The increase of the normalized J/psi yield with normalized dN(ch)/d eta is significantly stronger than linear and dependent on the transverse momentum. The data are compared to theoretical predictions, which describe the observed trends well, albeit not always quantitatively. (C) 2020 European Organization for Nuclear Research. Published by Elsevier B.V.Peer reviewe

Elliptic flow of charged particles at midrapidity relative to the spectator plane in Pb–Pb and Xe–Xe collisions

Measurements of the elliptic flow coefficient relative to the collision plane defined by the spectator neutrons v2{ SP} in collisions of Pb ions at center-of-mass energy per nucleon–nucleon pair √ 2.76 TeV and Xe ions at √ sNN = sNN =5.44 TeV are reported. The results are presented for charged particles produced at midrapidity as a function of centrality and transverse momentum for the 5–70% and 0.2–6 GeV/c ranges, respectively. The ratio between v2{ SP} and the elliptic flow coefficient relative to the participant plane v2{4}, estimated using four-particle correlations, deviates by up to 20% from unity depending on centrality. This observation differs strongly from the magnitude of the corresponding eccentricity ratios predicted by the TRENTo and the elliptic power models of initial state fluctuations that are tuned to describe the participant plane anisotropies. The differences can be interpreted as a decorrelation of the neutron spectator plane and the reaction plane because of fragmentation of the remnants from the colliding nuclei, which points to an incompleteness of current models describing the initial state fluctuations. A significant transverse momentum dependence of the ratio v2{ SP}/v2{4} is observed in all but the most central collisions, which may help to understand whether momentum anisotropies at low and intermediate transverse momentum have a common origin in initial state f luctuations. The ratios of v2{ SP} and v2{4} to the corresponding initial state eccentricities for Xe–Xe and Pb–Pb collisions at similar initial entropy density show a difference of (7.0 ±0.9)%with an additional variation of +1.8% when including RHIC data in the TRENTo parameter extraction. These observations provide new experimental constraints for viscous effects in the hydrodynamic modeling of the expanding quark–gluon plasma produced in heavy-ion collisions at the LHC

First measurement of Ωc0 production in pp collisions at s=13 TeV

The inclusive production of the charm–strange baryon 0 c is measured for the first time via its hadronic √ decay into −π+ at midrapidity (|y| &lt;0.5) in proton–proton (pp) collisions at the centre-of-mass energy s =13 TeV with the ALICE detector at the LHC. The transverse momentum (pT) differential cross section multiplied by the branching ratio is presented in the interval 2 &lt; pT &lt; 12 GeV/c. The pT dependence of the 0 c-baryon production relative to the prompt D0-meson and to the prompt 0 c-baryon production is compared to various models that take different hadronisation mechanisms into consideration. In the measured pT interval, the ratio of the pT-integrated cross sections of 0 c and prompt + c baryons multiplied by the −π+ branching ratio is found to be larger by a factor of about 20 with a significance of about 4σ when compared to e+e− collisions

Treatment of Aortoiliac Aneurysms: Compatibility of the E-liac Stent Graft (Artivion((R)), Iliac Branch Device) with Endurant II or IIs (Medtronic((R)), EVAR)

Purpose Iliac branch devices (IBD) are widely used to treat aortoiliac aneurysms with an unfit distal landing zone for standard endovascular aneurysm repair (EVAR). The aim of this retrospective study was to examine the treatment of aortoiliac aneurysms with the combination of the Endurant II(s) stent graft system (Medtronic((R))) and the E-liac stent graft (Artivion((R))).Materials and Methods Data of all patients who underwent an EVAR combined with unilateral or bilateral IBD between January 2015 and January 2020 were analyzed. Primary outcomes were technical success at implantation (successful EVAR with IBD extension placement and patency of the grafts without type 1 or type 3 endoleak), and type 1b/3 endoleak, hypogastric artery patency and IBD-related reinterventions during follow-up. Secondary outcomes were all type 1 endoleak, all reinterventions, rupture, and mortality during follow-up.Results A total of 38 patients were treated with a combination of EVAR with IBD. Technical success was 94.7% (n = 36/38). The 30-day survival was 100%. Median follow-up time was 31 months (range 8-56). During follow-up, no patients developed type 1b or type 3 endoleak and all hypogastric arteries at the side of IBD remained patent. The overall reintervention rate at 12 months follow-up was 5.3% (n = 2/38) and the IBD-related reintervention rate was 2.6% (n = 1/38).Conclusion The combination of the Endurant II(s) and the E-liac stent graft system is an effective and safe procedure for patients with an aortoiliac aneurysm. We confirm the high hypogastric artery patency rate using IBD. Furthermore, these devices have a high technical success rate even when it is combined with an Endurant II(s) EVAR main body

Clinical implementation of dual-source computed tomography for diagnostic cardiovascular angiography: Initial experience

Coronary angiography (CAG) has been the standard method for detection and follow-up of coronary artery disease for years. However, it has a slight but discrete complication rate. With the introduction of multidetector computed tomography (MDCT), the coronary system could be evaluated non-invasively. The limited temporal and spatial resolution of the first MDCT scanners made the examination quality of scanning of patients with high, increasing or irregular heart rates or patients with stents, clips or severely calcified arteries less predictable. The introduction of dual-source computed tomography (DSCT) might constitute a promising new concept for cardiac CT. In this study, we present our first experience with DSCT. We investigated seven patients for different indications with DSCT. Image quality was reliable in all patients despite the presence of high heart rates (up to 105 beats per minute), heavy calcifications and surgical clips. DSCT showed stenoses which were not detected on CAG. Regarding the fact that DSCT not only offers morphological information of the coronary vessel wall and lumen but also delivers all standard functional cardiac parameters, it has true potential as a routine diagnostic tool in the cardiac diagnostic workup. In conclusion, first results of DSCT show high-quality, consistent cardiac and coronary imaging independent of heart rate and patient condition. These features enable a breakthrough in non-invasive cardiac and coronary imagin

Excited-state spectroscopy on a nearly closed quantum dot via charge detection

We demonstrate a method for measuring the discrete energy spectrum of a quantum dot connected very weakly to a single lead. A train of voltage pulses applied to a metal gate induces tunneling of electrons between the quantum dot and a reservoir. The effective tunnel rate depends on the number and nature of the energy levels in the dot made accessible by the pulse. Measurement of the charge dynamics thus reveals the energy spectrum of the dot, as demonstrated for a dot in the few-electron regime.Kavli Institute of NanoscienceApplied Science