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The future Laser Interferometer Space Antenna (LISA) for gravitational wave detection in space and the precursor LISA Pathfinder missions rely on metal test masses (TMs) playing the role of free-falling geodesic-reference and interferometer end mirrors. Charge deposited on the TMs by high-energy particles of galactic and solar origin couples with stray electric fields thus perturbing the free-falling geodesic motion. In previous works it has been shown that sub-keV electrons play a relevant role for TM charging. In particular, electrons with energies below 100 eV show a wave-like behavior when impacting on the gold coatings of the TMs and electrode-housing (EH), the capacitive position sensor/actuator that surrounds the TMs. We aim at studying the effects of quantum diffraction of electrons on LISA Pathfinder and LISA TMs and EH gold lattice. We calculate the quantum diffraction probability of electrons with energies < 100 eV impinging on gold lattice from different directions by using the methods of quantum mechanics. The effects of electron quantum diffraction on LISA TM charging are reported here for the first time. This work is also of interest for the second-generation LISA-like space interferometers and for all space missions whose performance relies on free-falling metal test masses. • Spurious Coulomb forces act on the space interferomter metal test-masses due to the charging process induced by galactic cosmic rays and solar energetic particles. • Low-energy electromagnetic physics, lacking in the main Monte Carlo programs for particle propagation in matter, plays a major role for the estimate of the test-mass charging in space interferometers. • We calculate the probability of diffraction for electrons impacting on gold surfaces below 100 eV. • We apply the results of the calculation to the test-mass charging estimate for LISA. [ABSTRACT FROM AUTHOR]

A 29-year-old man presented to Emergency Department with nonspecific symptoms. Through a series of radiological and invasive diagnostic studies we finally reach an unexpected diagnosis of hypersentivity pneumonitis; this is a complex and heterogeneous disease which diagnosis can be challenging as its clinical, radiologic and histopathologic features overlap with those of other interstitial lung diseases (ILDs). Diagnosing an ILD is a dynamic process, and that is the reason why complex cases discussed in a multidisciplinary team may need to be reconsidered in light of evolution of the disease and the results of the performed exams with a flexible approach. [ABSTRACT FROM AUTHOR]