DAMPE (DArk Matter Particle Explorer) is a satellite-based experiment launched in December 2015 and smoothly taking data after five years of mission. The Silicon-Tungsten Tracker (STK) is ...characterized by 6 double layers of silicon micro-strip detectors, for a total detection area of 7 m
2
, and three 1 mm thick tungsten plates, placed in the mechanical support structure, aimed to the photon conversion in e
±
pairs. The STK has a double role: precise reconstruction of the track of charged particles with a spatial resolution around 40
μ
m for most incident angles of the incoming particles, identification of the charge of the incoming cosmic rays. The STK performances are excellent after five years of continuous operation in space: in this contribution the STK in-orbit calibration and performances during the whole DAMPE mission will be presented.
Penetrating particle ANalyzer (PAN) Wu, X.; Ambrosi, G.; Azzarello, P. ...
Advances in space research,
04/2019, Letnik:
63, Številka:
8
Journal Article
Recenzirano
Odprti dostop
PAN is a scientific instrument suitable for deep space and interplanetary missions. It can precisely measure and monitor the flux, composition, and direction of highly penetrating particles ...(>∼100 MeV/nucleon) in deep space, over at least one full solar cycle (11 years). The science program of PAN is multi- and cross-disciplinary, covering cosmic ray physics, solar physics, space weather and space travel. PAN will fill an observation gap of galactic cosmic rays in the GeV region, and provide precise information of the spectrum, composition and emission time of energetic particle originated from the Sun. The precise measurement and monitoring of the energetic particles is also a unique contribution to space weather studies. PAN will map the flux and composition of penetrating particles, which cannot be shielded effectively, precisely and continuously, providing valuable input for the assessment of the related health risk, and for the development of an adequate mitigation strategy. PAN has the potential to become a standard on-board instrument for deep space human travel.
PAN is based on the proven detection principle of a magnetic spectrometer, but with novel layout and detection concept. It will adopt advanced particle detection technologies and industrial processes optimized for deep space application. The device will require limited mass (20 kg) and power (20 W) budget. Dipole magnet sectors built from high field permanent magnet Halbach arrays, instrumented in a modular fashion with high resolution silicon strip detectors, allow to reach an energy resolution better than 10% for nuclei from H to Fe at 1 GeV/n. The charge of the particle, from 1 (proton) to 26 (Iron), can be determined by scintillating detectors and silicon strip detectors, with readout ASICs of large dynamic range. Silicon pixel detectors used in a low power setting will maintain the detection capabilities for even the strongest solar events. A fast scintillator with silicon photomultiplier (SiPM) readout will provide timing information to determine the entering direction of the particle, as well as a high rate particle counter. Low noise, low power and high density ASIC will be developed to satisfy the stringent requirement of the position resolution and the power consumption of the tracker.
DAMPE is a satellite-borne experiment aimed to probe astroparticle physics in the GeV-TeV energy range. The Silicon tracker (STK) is one of the key components of DAMPE, which allows the ...reconstruction of trajectories (tracks) of detected particles. The non-negligible amount of material in the tracker poses a challenge to its reconstruction and alignment. In this paper we describe methods to address this challenge. We present the track reconstruction algorithm and give insight into the alignment algorithm. We also present our CAD-to-GDML converter, an in-house tool for implementing detector geometry in the software from the CAD drawings of the detector.
We report on the performance of planar silicon diodes operating in the double injection mode and emitting modulated infrared radiation at temperature range above 300
K. Results present theoretical ...analysis and experimental verification of an optimization aimed at maximal difference between emissivity of this structure for cases with and without forward bias applied to
p–
n junction. Several advantages of the structures were shown: wide emission spectrum (3÷12
μm), short rise-fall time (300
μs), high operating temperature (≈400
K). These planar photonic sources can be used as easily controlled sources of modulated infrared radiation in wide spectral range, image simulators, e.g. dynamic scene simulation devices with frame frequencies well above 200
Hz and for measurements of thermovision camera dynamic parameters.
High-energy cosmic-ray electrons and positrons (CREs), which lose energy quickly during their propagation, provide a probe of Galactic high-energy processes and may enable the observation of ...phenomena such as dark-matter particle annihilation or decay. The CRE spectrum has been measured directly up to approximately 2 teraelectronvolts in previous balloon- or space-borne experiments, and indirectly up to approximately 5 teraelectronvolts using ground-based Cherenkov γ-ray telescope arrays. Evidence for a spectral break in the teraelectronvolt energy range has been provided by indirect measurements, although the results were qualified by sizeable systematic uncertainties. Here we report a direct measurement of CREs in the energy range 25 gigaelectronvolts to 4.6 teraelectronvolts by the Dark Matter Particle Explorer (DAMPE) with unprecedentedly high energy resolution and low background. The largest part of the spectrum can be well fitted by a 'smoothly broken power-law' model rather than a single power-law model. The direct detection of a spectral break at about 0.9 teraelectronvolts confirms the evidence found by previous indirect measurements, clarifies the behaviour of the CRE spectrum at energies above 1 teraelectronvolt and sheds light on the physical origin of the sub-teraelectronvolt CREs.
In this paper we deal with the problem of predicting a steady-state neutron spectrum in media of arbitrary composition and geometry. The analytical calculations of such spectrum are often too ...complex, if at all possible. We describe a method of Geant4-based Monte Carlo calculation of the steady-state neutron spectrum in a medium containing a fixed neutron source. In addition to the steady-state spectrum, we obtain the snapshots of the neutron spectrum evolution in time, which may be thought of as the non-equilibrium neutron spectra, and their form is of considerable interest for further studies.
•The steady-state neutron spectrum is crucial for numerous applications.•We develop a method of steady-state neutron spectrum calculation using GEANT4.•We discuss some optimizations and present some successful tests.•The neutron spectrum evolution in time is obtained as a bonus.
The DArk Matter Particle Explorer (DAMPE), one of the four scientific space science missions within the framework of the Strategic Pioneer Program on Space Science of the Chinese Academy of Sciences, ...is a general purpose high energy cosmic-ray and gamma-ray observatory, which was successfully launched on December 17th, 2015 from the Jiuquan Satellite Launch Center. The DAMPE scientific objectives include the study of galactic cosmic rays up to ∼ 10 TeV and hundreds of TeV for electrons/gammas and nuclei respectively, and the search for dark matter signatures in their spectra. In this paper we illustrate the layout of the DAMPE instrument, and discuss the results of beam tests and calibrations performed on ground. Finally we present the expected performance in space and give an overview of the mission key scientific goals.
The precise measurement of the spectrum of protons, the most abundant component of the cosmic radiation, is necessary to understand the source and acceleration of cosmic rays in the Milky Way. This ...work reports the measurement of the cosmic ray proton fluxes with kinetic energies from 40 GeV to 100 TeV, with 2
/
years of data recorded by the DArk Matter Particle Explorer (DAMPE). This is the first time that an experiment directly measures the cosmic ray protons up to ~100 TeV with high statistics. The measured spectrum confirms the spectral hardening at ~300 GeV found by previous experiments and reveals a softening at ~13.6 TeV, with the spectral index changing from ~2.60 to ~2.85. Our result suggests the existence of a new spectral feature of cosmic rays at energies lower than the so-called knee and sheds new light on the origin of Galactic cosmic rays.
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