arXiv subjects

Fabrizio Grosa

Publications and source records attributed to Fabrizio Grosa.

4 recordsLinked to original sources

arXiv2026

Charge sharing and alignment performance of bent ALPIDEs measured with low-energy protons

The upgrade of the ALICE experiments Inner Tracking System (ITS3) aims to replace its innermost detection layers with bent wafer-scale CMOS MAPS sensors. This study examines the performance of ALPIDE chips, currently used in the ALICE ITS2, when operated in a bent configuration under realistic experimental conditions. Proton beams with energies of 80 MeV, 120 MeV and 200 MeV were used to study proton-proton elastic scattering on a polypropylene fiber target reconstructed using two opposing arms of trackers with sensors bent to radii of 18 mm, 24 mm and 30 mm. The measured low-momentum protons provided a testbed for investigating clustering behavior in high-energy loss events, where no significant impact of bending was observed on cluster size. Additionally, alignment strategies for bent detectors were evaluated using the distance of closest approach (DCA) and opening angle between scattered proton tracks as benchmarks. The achieved resolution matches expectations from simulations, confirming the suitability of bent MAPS sensors for future high-energy and nuclear physics applications.

physics.ins-det↗

arXiv2019

Study of $\pmb{R_{\rm AA}}$ and $\pmb{v_2}$ of non-strange D mesons and D-jet production in Pb-Pb collisions with ALICE

Heavy quarks are sensitive probes of the colour-deconfined medium formed in ultra-relativistic heavy-ion collisions, the Quark-Gluon Plasma (QGP). The ALICE Collaboration measured the production of $\rm D^0$, $\rm D^+$, and $\rm D^{*+}$ mesons in Pb-Pb collisions at $\sqrt{s_{\rm NN}}=5.02$ TeV. The properties of the in-medium energy loss are investigated via the measurement of the nuclear modification factor ($R_{\rm AA}$) of non-strange D mesons. The modification of the D-meson transverse momentum ($p_{\rm T}$) distributions inside the jet is studied via the measurement of the D-meson tagged jet $R_{\rm AA}$ in central Pb-Pb collisions. In mid-central collisions, the measurement of the D-meson elliptic flow ($v_2$) at low and intermediate $p_{\rm T}$ gives insight into the participation of the charm quark in the collective motion of the system, while at high $p_{\rm T}$ it constrains the path-length dependence of the energy loss. The coupling of the charm quark to the light quarks in the underlying medium is further investigated with the application of the event-shape engineering (ESE) technique to D-meson elliptic flow.

nucl-ex↗

arXiv2018

Measurement of D-meson nuclear modification factor and flow in Pb--Pb collisions with ALICE at the LHC

Heavy quarks are sensitive probes of the colour-deconfined medium formed in ultra-relativistic heavy-ion collisions, the Quark-Gluon Plasma (QGP). The ALICE Collaboration measured the production of ${\rm D}^0$, ${\rm D}^+$, ${\rm D}^{*+}$ and ${\rm D_s}^+$ mesons in Pb-Pb collisions at $\sqrt{s_{\rm NN}}=5.02~{\rm TeV}$. The properties of the in-medium energy loss and the possible modification of the charm-quark hadronisation mechanism are investigated via the measurement of the nuclear modification factor ($R_{\rm AA}$) of non-strange and strange D mesons. In mid-central collisions, the measurement of the D-meson elliptic flow ($v_2$) at low and intermediate transverse momentum ($p_{\rm T}$) gives insight into the participation of the charm quark in the collective motion of the system, while at high $p_{\rm T}$ it constrains the path-length dependence of the energy loss. The coupling of the charm quark to the light quarks in the underlying medium is further investigated with the application of the event-shape engineering (ESE) technique to D-meson elliptic flow. Finally, the role of the early magnetic field created in heavy-ion collisions is studied via the first measurement at the LHC energies of the charged-dependent directed flow ($v_1$) of ${\rm D}^0$ mesons as a function of pseudorapidity.

nucl-ex↗

arXiv2018

Measurement of the D-meson nuclear modification factor and elliptic flow in Pb-Pb collisions at $\sqrt{s_{\rm NN}}=5.02~{\rm TeV}$ with ALICE at the LHC

Heavy-flavour hadrons are recognised as a powerful probe for the characterisation of the deconfined medium created in heavy-ion collisions, the Quark-Gluon Plasma (QGP). The ALICE Collaboration measured the production of ${\rm D}^{0}$, ${\rm D}^{+}$, ${\rm D}^*$ and ${\rm D_s}^{+}$ mesons in Pb-Pb collisions at $\sqrt{s_{\rm NN}}=5.02~{\rm TeV}$. The measurement of the nuclear modification factor ($R_{\rm AA}$) provides a strong evidence of the in-medium parton energy loss. The comparison between the ${\rm D_s}^{+}$ and the non-strange D-meson $R_{\rm AA}$ can help to study the hadronisation mechanism of the charm quark in the QGP. In mid-central collisions, the measurement of the D-meson elliptic flow $v_2$ at low transverse momentum ($p_{\rm T}$) gives insight into the participation of the charm quark into the collective motion of the system, while at high $p_{\rm T}$ it constrains the path-length dependence of the energy loss. The ${\rm D_s}^{+}$ $v_2$, measured for the first time at the LHC, is found to be compatible to that of non-strange D mesons and positive with a significance of about $2.6~σ$. Further evidence of a strong coupling of the charm quark to the light quarks of the underlying medium is suggested by the first application of the Event-Shape Engineering (ESE) technique to D-meson elliptic flow.

nucl-ex↗