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Abstract.A cooled and mechanically retractable beryllium filter has been installed and commissioned on the low-energy OSIRIS spectrometer at ISIS. This instrument development extends the energy-transfer range of the spectrometer up to ca. 20 meV (∼ 5 THz), leading to an excellent resolution at THz frequencies and substantial gains in detected flux relative to existing capabilities on the neighbouring IRIS spectrometer. Herein, we provide a concise account of this new capability for highresolution neutron spectroscopy in the THz domain, as well as outline a number of ongoing and potential scientific opportunities in condensed-matter physics, chemistry, and materials science. The reasons whyOSIRIS is an indirect-geometry neutron spectrometer with long-wavelength diffraction capabilities [1]. The secondary spectrometer sits at ca. 34 m from a 25 K liquid-hydrogen (H 2 ) moderator on ISIS Target Station I. Optimised for low-energy, high-resolution inelastic neutron-scattering studies, OSIRIS uses a broad band of incident wavelengths which are Bragg-scattered from a crystal-analyser array following interaction with the sample under investigation. Owing to the pulsed nature of the source, time-of-flight methods are used to determine energy transfer at a particular scattering angle.As the last of first-generation instruments built at ISIS, OSIRIS has been operational since 1997. A schematic diagram of the instrument is shown in Fig. 1. In the early days, its primary use was as a long-dspacing diffractometer, exploiting its dedicated, 960-pixel backscattering detector bank with a resolution as high as d/d = 2.5 × 10 −3 and a dynamic range extending up to 20Å. In 2003, the instrument was upgraded with a cooled pyrolytic graphite (PG) analyser bank, thereby paving the way for low-energy inelastic and quasielastic neutron-scattering studies [3]. Its primary spectrometer profited from early advances in neutronguide technology in the 1990s, with an m = 2 guide extending across the majority of its primary length, and terminated by an m = 3.5 focusing section immediately prior to the sample. In spectroscopic mode, OSIRIS uses PG crystals cooled to 10 K so as to define two primary final energies using PG002 (E f = 1.84 meV) and PG004 (E f = 7.38 meV) Bragg reflections. The spectral resolution a Corresponding author: F. Demmel (franz.demmel@stfc. ac.uk) b and F. Fernandwz-Alonso(felix.fernandez-alonso@stfc. ac.uk) of these two alternative settings amounts to 25 and 99 µeV for PG002 and PG004, respectively. Recent Monte Carlo simulations of the instrument have also provided important insights into its neutronic performance, including the various contributions to the resolution function and line shape [2]. As on similar neutron spectrometers like IRIS at ISIS [4] or, more recently, BASIS at SNS [5] or DNA at JPARC [6], a tight spectral resolution in the µeV domain comes as a result of several factors, including: a relatively long flight path (>30 m) at a short-pulse spallation source; tight incident neutron pulses from a cold neut...

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In the summer of 1990, Montreal’s alternative queer community came together in response to a police raid on an after-hours party, and arrests during subsequent clashes. Reviewing the video evidence that exists of the events surrounding the Sex Garage raid, as well as newspaper articles and news features, the authors found that a reductionist story had coalesced out of the multiple and varying experiences of the activisms around the incidents, spooling them into a unified narrative. In this essay, the authors unspool this singular narrative through their dialogic reflections on their different experiences of Sex Garage, and not only offer alternate stories of the events surrounding Sex Garage, but also demonstrate one attempt at rethinking the ways that the authors both tell and write the stories of their histories.