Silicon Drift Detectors’ Spectroscopic Response during the SIDDHARTA-2 Kaonic Helium Run at the DAΦNE Collider

M Miliucci ,Francesco Sgaramella,Szymon Niedźwiecki,Pietro King,Marco Carminati,M Bazzi ,M Silarski ,D Bosnar ,K Piscicchia ,J Márton ,C Guaraldo ,P Moskal ,P Levi Sandri ,A Clozza ,G Deda ,H Shi ,D Sirghi ,M Tüchler ,F Sirghi ,M Cargnelli ,O Vázquez Doce ,C Fiorini ,R Del Grande ,M Iliescu ,A Spallone ,F Napolitano ,M Bragadireanu ,M Iwasaki ,L De Paolis ,C Curceanu ,M Skurzok ,A Scordo ,J Zmeskal

doi:10.3390/condmat6040047

Abstract

A large-area silicon drift detectors (SDDs) system has been developed by the SIDDHARTA-2 collaboration for high precision light kaonic atom X-ray spectroscopy at the DAΦNE collider of Istituto Nazionale di Fisica Nucleare—Laboratori Nazionali di Frascati. The SDDs’ geometry and electric field configuration, combined with their read-out electronics, make these devices suitable for performing high precision light kaonic atom spectroscopy measurements in the background of the DAΦNE collider. This work presents the spectroscopic response of the SDDs system during the first exotic atoms run of SIDDHARTA-2 with kaonic helium, a preliminary to the kaonic deuterium data taking campaign. The SIDDHARTA-2 spectroscopic system has good energy resolution and a 2 μs timing window which rejects the asynchronous events, scaling the background by a factor of 10−5. The results obtained for the first exotic atoms run of SIDDHARTA-2 prove this system to be ready to perform the challenging kaonic deuterium measurement.

Highlights

Silicon drift detector (SDD) technology [1,2] combines the silicon p–n junction reverse bias properties with an innovative electronic field design, resulting in low electric noise and high-rate devices able to perform high precision X-ray measurements for a wide rangeCondens
The SIDDHARTA-2 SDDs system X-ray response was evaluated during the K− He4 data taking campaign, prior to the kaonic deuterium measurement
The SIDDHARTA-2 collaboration developed a silicon drift detectors (SDDs) system dedicated to ambitious shift (e) and width (Γ) measurements of the K− d 2p → 1s transition

Summary

Introduction

Silicon drift detector (SDD) technology [1,2] combines the silicon p–n junction reverse bias properties with an innovative electronic field design, resulting in low electric noise and high-rate devices able to perform high precision X-ray measurements for a wide range. The SDDs’ excellent spectroscopic performances are used for light kaonic atom X-ray spectroscopy to accurately determine shifts (e) and widths (Γ) of the atomic levels caused by the KN strong interaction. These measurements allow one to probe the non-perturbative quantum chromodynamics (QCD) in the strangeness sector, with implications extending from particle and nuclear physics to astrophysics [8,9,10,11]. The signals corresponding to the kaonic deuterium K-transitions are expected to be within 4000–12,000 eV, perfectly matching with the SDDs’ high quantum efficiency (above 85% for 450 μm thick silicon bulk) To achieve this unprecedented and ambitious goal, the SIDDHARTA-2 collaboration developed a SDDs system dedicated to kaonic deuterium X-ray spectroscopy measurements. This work presents the SIDDHARTA-2 experimental apparatus and the SDDs system’s X-ray spectroscopy response during the first phase of the kaonic helium data taking campaign, prior to the difficult kaonic deuterium measurement

The SIDDHARTA-2 Experiment

Results and Discussion

Conclusions