arXiv subjects

Giovanni Carboni

Publications and source records attributed to Giovanni Carboni.

5 recordsLinked to original sources

arXiv2014

Micronucleus induction by 915 MHz Radiofrequency Radiation in Vicia faba root tips

The mutagenic effect of radiofrequency electromagnetic field (RF-EMF) is evaluated by the micronucleus (MN) test in secondary roots of Vicia faba seedlings. Root exposures were carried out with 915 MHz continuous wave (CW) radiation for 72h, at power densities of 25, 38, 50 W/m$^2$. The specific absorption rate (SAR) corresponding to the experimental exposures was measured with a calorimetric method and fall in the range 0.3-1.8 W/kg. Results show a significant increase of MN frequency up to ten fold, correlated with the increasing power densities values.

q-bio.QM↗

arXiv2010

Status of LHCb

The status of the LHCb experiment is presented. The experiment has been taking data since the LHC startup. The performances of the various sub-detectors are discussed and a preliminary measurement of the b cross-section is reported. The value is in agreement with expectations.

hep-ex↗

arXiv2003

New results from an extensive aging test on bakelite Resistive Plate Chambers

We present recent results of an extensive aging test, performed at the CERN Gamma Irradiation Facility on two single--gap RPC prototypes, developed for the LHCb Muon System. With a method based on a model describing the behaviour of an RPC under high particle flux conditions, we have periodically measured the electrode resistance R of the two RPC prototypes over three years: we observe a large spontaneous increase of R with time, from the initial value of about 2 MOhm to more than 250 MOhm. A corresponding degradation of the RPC rate capabilities, from more than 3 kHz/cm2 to less than 0.15 kHz/cm2 is also found.

physics.ins-det↗

arXiv2003

First results from an aging test of a prototype RPC for the LHCb Muon System

Recent results of an aging test performed at the CERN Gamma Irradiation Facility on a single--gap RPC prototype developed for the LHCb Muon System are presented. The results are based on an accumulated charge of about 0.45 C/cm$^2$, corresponding to about 4 years of LHCb running at the highest background rate. The performance of the chamber has been studied under several photon flux values exploiting a muon beam. A degradation of the rate capability above 1 kHz/cm$^2$ is observed, which can be correlated to a sizeable increase of resistivity of the chamber plates. An increase of the chamber dark current is also observed. The chamber performance is found to fulfill the LHCb operation requirements.

physics.ins-det↗

arXiv2002

Preliminary results of an aging test of RPC chambers for the LHCb Muon System

The preliminary results of an aging test performed at the CERN Gamma Irradiation Facility on a single--gap RPC prototype developed for the LHCb Muon System are presented. The results are based on an accumulated charge density of 0.42 C/cm^2, corresponding to about 4 years of LHCb running at the highest background rate. We observe a rise in the dark current and noise measured with source off. The current drawn with source on steadily decreased, possibly indicating an increase of resistivity of the chamber plates. The performance of the chamber, studied with a muon beam under several photon flux values, is found to still fulfill the LHCb operation requirements.

physics.ins-det↗