The large area detector onboard the eXTP mission

The Large Area Detector (LAD) is the high-throughput, spectral-timing instrument onboard the eXTP mission, a flagship mission of the Chinese Academy of Sciences and the China National Space Administration, with a large European participation coordinated by Italy and Spain. The eXTP mission is currently performing its phase B study, with a target launch at the end-2027. The eXTP scientific payload includes four instruments (SFA, PFA, LAD and WFM) offering unprecedented simultaneous wide-band X-ray timing and polarimetry sensitivity. The LAD instrument is based on the design originally proposed for the LOFT mission. It envisages a deployed 3.2 m2 effective area in the 2-30 keV energy range, achieved through the technology of the large-area Silicon Drift Detectors - offering a spectral resolution of up to 200 eV FWHM at 6 keV - and of capillary plate collimators - limiting the field of view to about 1 degree. In this paper we will provide an overview of the LAD instrument design, its current status of development and anticipated performance

The XGIS instrument on-board THESEUS: the detection plane and on-board electronics

The X and Gamma Imaging Spectrometer instrument on-board the THESEUS mission (selected by ESA in the framework of the Cosmic Vision M5 launch opportunity, currently in phase A) is based on a detection plane composed of several thousands of single active elements. Each element comprises a 4.5x4.5x30 mm 3 CsI(Tl) scintillator bar, optically coupled at both ends to Silicon Drift Detectors (SDDs). The SDDs acts both as photodetectors for the scintillation light and as direct X-ray sensors. In this paper the design of the XGIS detection plane is reviewed, outlining the strategic choices in terms of modularity and redundancy of the system. Results on detector-electronics prototypes are also described. Moreover, the design and development of the low-noise front-end electronics is presented, emphasizing the innovative architectural design based on custom-designed Application-Specific Integrated Circuits (ASICs).Comment: Proceedings of the SPIE 2020, paper 11444-27

Design, integration, and test of the scientific payloads on-board the HERMES constellation and the SpIRIT mission

HERMES (high energy rapid modular ensemble of satellites) is a space-borne mission based on a constellation of nano-satellites flying in a low-Earth orbit (LEO). The six 3U CubeSat buses host new miniaturized instruments hosting a hybrid silicon drift detector/GAGG:Ce scintillator photodetector system sensitive to x-rays and gamma-rays. HERMES will probe the temporal emission of bright high-energy transients such as gamma-ray bursts (GRBs), ensuring a fast transient localization (with arcmin-level accuracy) in a field of view of several steradians exploiting the triangulation technique. With a foreseen launch date in late 2023, HERMES transient monitoring represents a keystone capability to complement the next generation of gravitational wave experiments. Moreover, the HERMES constellation will operate in conjunction with the space industry responsive intelligent thermal (SpIRIT) 6U CubeSat, to be launched in early 2023. SpIRIT is an Australian-Italian mission for high-energy astrophysics that will carry in a sun-synchronous orbit (SSO) an actively cooled HERMES detector system payload. On behalf of the HERMES collaboration, in this paper we will illustrate the HERMES and SpIRIT payload design, integration and tests, highlighting the technical solutions adopted to allow a wide-energy-band and sensitive x-ray and gamma-ray detector to be accommodated in a 1U CubeSat volume

The wide field monitor onboard the Chinese-European x-ray mission eXTP

The eXTP (enhanced X-ray Timing and Polarimetry) mission is a major project of the Chinese Academy of Sciences (CAS), with a large involvement of Europe. The scientific payload of eXTP includes four instruments: the SFA (Spectroscopy Focusing Array) and the PFA (Polarimetry Focusing Array) - led by China - the LAD (Large Area Detector) and the WFM (Wide Field Monitor) - led by Europe (Italy and Spain). They offer a unique simultaneous wide-band X-ray timing and polarimetry sensitivity. The WFM is a wide field X-ray monitor instrument in the 2-50 keV energy range, consisting of an array of six coded mask cameras with a field of view of 180ºx90ºat an angular resolution of 5 arcmin and 4 silicon drift detectors in each camera. Its unprecedented combination of large field of view and imaging down to 2 keV will allow eXTP to make important discoveries of the variable and transient X-ray sky and is essential in detecting transient black holes, that are part of the primary science goals of eXTP, so that they can be promptly followed up with other instruments on eXTP and elsewhere

The large area detector onboard the eXTP mission

The Large Area Detector (LAD) is the high-throughput, spectral-timing instrument onboard the eXTP mission, a flagship mission of the Chinese Academy of Sciences and the China National Space Administration, with a large European participation coordinated by Italy and Spain. The eXTP mission is currently performing its phase B study, with a target launch at the end-2027. The eXTP scientific payload includes four instruments (SFA, PFA, LAD and WFM) offering unprecedented simultaneous wide-band X-ray timing and polarimetry sensitivity. The LAD instrument is based on the design originally proposed for the LOFT mission. It envisages a deployed 3.2 m2 effective area in the 2-30 keV energy range, achieved through the technology of the large-area Silicon Drift Detectors - offering a spectral resolution of up to 200 eV FWHM at 6 keV - and of capillary plate collimators - limiting the field of view to about 1 degree. In this paper we will provide an overview of the LAD instrument design, its current status of development and anticipated performance