Rubin-LSST

Abstract:

We present simultaneous radio through sub-mm observations of the black hole X-ray binary (BHXB) V404 Cygni during the most active phase of its June 2015 outburst. Our 4 h long set of overlapping observations with the Very Large Array, the Sub-millimeter Array and the James Clerk Maxwell Telescope (SCUBA-2) covers eight different frequency bands (including the first detection of aBHXBjet at 666 GHz/450 μm), providing an unprecedented multifrequency view of the extraordinary flaring activity seen during this period of the outburst. In particular, we detect multiple rapidly evolving flares, which reach Jy-level fluxes across all of our frequency bands. With this rich data set, we performed detailed MCMC modelling of the repeated flaring events. Our custom model adapts the van der Laan synchrotron bubble model to include twin bi-polar ejections, propagating away from the black hole at bulk relativistic velocities, along a jet axis that is inclined to the line of sight. The emission predicted by our model accounts for projection effects, relativistic beaming and the geometric time delay between the approaching and receding ejecta in each ejection event. We find that a total of eight bi-polar, discrete jet ejection events can reproduce the emission that we observe in all of our frequency bands remarkably well.With our best-fitting model, we provide detailed probes of jet speed, structure, energetics and geometry. Our analysis demonstrates the paramount importance of the mm/sub-mm bands, which offer a unique, more detailed view of the jet than can be provided by radio frequencies alone.

Abstract:

The shape and size of the stored charge packet within a CCD pixel after exposure has implications for optimal device operation, susceptibility to radiation damage and modelling of dynamic charge collection effects such as the “Brighter-Fatter Effect”. Above the full well capacity, phenomena such as bleed trails and surface charge loss occur. In this paper we discuss why accurately reproducing saturation effects in simulations based on electrostatics is difficult, and present an approach to modelling the storage of charge in CCD pixels using commercial semiconductor simulation software. We suggest experimental measurements which can be connected to such modelling. Full well measurements on a thick, high resistivity back illuminated sensor (the e2v CCD261) are presented.

Abstract:

During 2015 the ATLAS experiment recorded 3.8 fb^−1 of proton–proton collision data at a centre-of-mass energy of 13 TeV. The ATLAS trigger system is a crucial component of the experiment, responsible for selecting events of interest at a recording rate of approximately 1 kHz from up to 40 MHz of collisions. This paper presents a short overview of the changes to the trigger and data acquisition systems during the first long shutdown of the LHCand shows the performance of the trigger system and its components based on the 2015 proton–proton collision data.