Search

This work presents the design and preliminary performance of a highly-multiplexed superconducting detector readout. The readout system is implemented on the Xilinx ZCU111 RFSoC Evaluation Board. The current design uses 12% of the DSPs, 60% of the LUTs, 20% of the FFs, and 30% of the BRAM and makes timing at 512 MHz. The system uses two integrated ADCs and DACs running at 4.096 GSPS to read out 2,048 superconducting detectors. This work targets a 2x increase in the number of superconducting detectors processed per board with 80% less power than previous readout schemes. The open-source design leverages modern FPGA productivity tools including Vivado High-Level Synthesis to create all custom IP blocks, PYNQ to test and verify individual IP and develop Python drivers, and Vivado ML Intelligent Design Runs to close timing. We emphasize strategies for achieving timing closure without custom HDL which we expect to be useful for superconducting device groups looking to utilize FPGAs in high-performance applications without specialized knowledge in FPGA design., Comment: 30th IEEE International Symposium On Field-Programmable Custom Computing Machines (accepted as poster)

Galaxy clusters trace the largest structures of the Universe and provide ideal laboratories for studying galaxy evolution and cosmology. Clusters with extended X-ray emission have been discovered at redshifts up to z ~ 2.5. Meanwhile, there has been growing interest in hunting for protoclusters, the progenitors of clusters, at higher redshifts. It is, however, very challenging to find the largest protoclusters at early times when they start to assemble. Here we report a giant protocluster of galaxies at redshift z = 5.7, when the Universe was only one billion years old. This protocluster occupies a volume of about 35x35x35 cubic co-moving megaparsecs. It is embedded in an even larger overdense region with at least 41 spectroscopically confirmed, luminous Lyman-alpha emitting galaxies (Lyman-alpha Emitters, or LAEs), including several previously reported LAEs. Its LAE density is 6.6 times the average density at z ~ 5.7. It is the only one of its kind in an LAE survey in four square degrees on the sky. Such a large structure is also rarely seen in current cosmological simulations. This protocluster will collapse into a galaxy cluster with a mass of (3.6+/-0.9) x 10^{15} solar masses, comparable to those of the most massive clusters or protoclusters known to date., Published in Nature Astronomy on Oct 15, 2018 (DOI: 10.1038/s41550-018-0587-9)

We present an exhaustive census of Lyman alpha (Ly$��$) emission in the general galaxy population at $37$., Accepted for publication in ApJ; Figure 3 updated

We present a spectroscopic survey of high-redshift, luminous galaxies over four square degrees on the sky, aiming to build a large and homogeneous sample of Ly$��$ emitters (LAEs) at $z\approx5.7$ and 6.5, and Lyman-break galaxies (LBGs) at $5.5, 18 pages, 11 figures, Accepted for publication in The Astrophysical Journal

We present results from high resolution optical spectra toward 66 young stars in the Orion B molecular cloud to study their kinematics and other properties. Observations of the H$��$ and Li I 6707 �� lines are used to check membership and accretion properties. While the stellar radial velocities of in NGC 2068 and L1622 show good agreement with that of the molecular gas, many of the stars in NGC 2024 show a considerable offset. This could be a signature of either expansion of the cluster, high degree of the ejection of the stars from the cluster through the dynamical interaction, or the acceleration of the gas due to stellar feedback., Accepted to ApJ; 8 pages, 9 figures

We measure the photometric rotation periods of the components of multiple systems in young stellar associations to investigate the causes of the observed rotation period dispersion. We present the case of the wide binary AG Tri in the 23-Myr young beta Pictoris Association consisting of K4 + M1 dwarfs. Our multi-band, multi-season photometric monitoring allowed us to measure the rotation periods of both components P_A = 12.4d and P_B = 4.66d, to detect a prominent magnetic activity in the photosphere, likely responsible for the measured radial velocity variations, and for the first time, a flare event on the M1 component AG Tri B. We investigate either the possibility that the faster rotating component may have suffered an enhanced primordial disc dispersal, starting its PMS spin-up earlier than the slower rotating component, or the possibility that the formation of a debris disc may have prevented AG Tri A from gaining part of the angular momentum from the accreting disc., 28 pages, 7 figures, accepted for publication in Astrophysics and Space Science 2015, (ASTR-D-15-00445R2)