@inproceedings{10725, abstract = {Bilayer graphene with ~ 1.1 degrees twist mismatch between the layers hosts a low energy flat band in which the Coulomb interaction is large relative to the bandwidth, promoting correlated insulating states at half band filling, and superconducting (SC) phases with dome-like structure neighboring correlated insulating states. Here we show measurements of a dual-graphite-gated twisted bilayer graphene device, which minimizes charge inhomogeneity. We observe new correlated phases, including for the first time a SC pocket near half-filling of the electron-doped band and resistive states at quarter-filling of both bands that emerge in a magnetic field. Changing the layer polarization with vertical electric field reveals an unexpected competition between SC and correlated insulator phases, which we interpret to result from differences in disorder of each graphene layer and underscores the spatial inhomogeneity like twist angle as a significant source of disorder in these devices [1].}, author = {Chen, Shaowen and Yankowitz, Matthew and Polshyn, Hryhoriy and Watanabe, Kenji and Taniguchi, Takashi and Graf, David E. and Young, Andrea and Dean, Cory R.}, booktitle = {APS March Meeting 2019}, issn = {0003-0503}, location = {Boston, MA, United States}, number = {2}, publisher = {American Physical Society}, title = {{Correlated insulating and superconducting phases in twisted bilayer graphene}}, volume = {64}, year = {2019}, } @inproceedings{10723, abstract = {In monolayer graphene, the interplay of electronic correlations with the internal spin- and valley- degrees of freedom leads to a complex phase diagram of isospin symmetry breaking at high magnetic fields. Recently, Wei et al. (Science (2018)) demonstrated that spin waves can be electrically generated and detected in graphene heterojunctions, allowing direct experiment access to the spin degree of freedom. Here, we apply this technique to high quality graphite-gated graphene devices showing robust fractional quantum Hall phases and isospin phase transitions. We use an edgeless Corbino geometry to eliminate the contributions of edge states to the spin-wave mediated nonlocal voltage, allowing unambiguous identification of spin wave transport signatures. Our data reveal two phases within the ν = 1 plateau. For exactly ν=1, charge is localized but spin waves propagate freely while small carrier doping completely quenches the low-energy spin-wave transport, even as those charges remain localized. We identify this new phase as a spin textured electron solid. We also find that spin-wave transport is modulated by phase transitions in the valley order that preserve spin polarization, suggesting that this technique is sensitive to both spin and valley order.}, author = {Zhou, Haoxin and Polshyn, Hryhoriy and Tanaguchi, Takashi and Watanabe, Kenji and Young, Andrea}, booktitle = {APS March Meeting 2019}, issn = {0003-0503}, location = {Boston, MA, United States}, number = {2}, publisher = {American Physical Society}, title = {{Spin wave transport through electron solids and fractional quantum Hall liquids in graphene}}, volume = {64}, year = {2019}, } @inproceedings{10877, abstract = {This report presents the results of a friendly competition for formal verification of continuous and hybrid systems with piecewise constant dynamics. The friendly competition took place as part of the workshop Applied Verification for Continuous and Hybrid Systems (ARCH) in 2019. In this third edition, six tools have been applied to solve five different benchmark problems in the category for piecewise constant dynamics: BACH, Lyse, Hy- COMP, PHAVer/SX, PHAVerLite, and VeriSiMPL. Compared to last year, a new tool has participated (HyCOMP) and PHAVerLite has replaced PHAVer-lite. The result is a snap- shot of the current landscape of tools and the types of benchmarks they are particularly suited for. Due to the diversity of problems, we are not ranking tools, yet the presented results probably provide the most complete assessment of tools for the safety verification of continuous and hybrid systems with piecewise constant dynamics up to this date.}, author = {Frehse, Goran and Abate, Alessandro and Adzkiya, Dieky and Becchi, Anna and Bu, Lei and Cimatti, Alessandro and Giacobbe, Mirco and Griggio, Alberto and Mover, Sergio and Mufid, Muhammad Syifa'ul and Riouak, Idriss and Tonetta, Stefano and Zaffanella, Enea}, booktitle = {ARCH19. 6th International Workshop on Applied Verification of Continuous and Hybrid Systems}, editor = {Frehse, Goran and Althoff, Matthias}, issn = {2398-7340}, location = {Montreal, Canada}, pages = {1--13}, publisher = {EasyChair}, title = {{ARCH-COMP19 Category Report: Hybrid systems with piecewise constant dynamics}}, doi = {10.29007/rjwn}, volume = {61}, year = {2019}, } @article{11061, abstract = {Many adult tissues contain postmitotic cells as old as the host organism. The only organelle that does not turn over in these cells is the nucleus, and its maintenance represents a formidable challenge, as it harbors regulatory proteins that persist throughout adulthood. Here we developed strategies to visualize two classes of such long-lived proteins, histones and nucleoporins, to understand the function of protein longevity in nuclear maintenance. Genome-wide mapping of histones revealed specific enrichment of long-lived variants at silent gene loci. Interestingly, nuclear pores are maintained by piecemeal replacement of subunits, resulting in mosaic complexes composed of polypeptides with vastly different ages. In contrast, nondividing quiescent cells remove old nuclear pores in an ESCRT-dependent manner. Our findings reveal distinct molecular strategies of nuclear maintenance, linking lifelong protein persistence to gene regulation and nuclear integrity.}, author = {Toyama, Brandon H. and Arrojo e Drigo, Rafael and Lev-Ram, Varda and Ramachandra, Ranjan and Deerinck, Thomas J. and Lechene, Claude and Ellisman, Mark H. and HETZER, Martin W}, issn = {1540-8140}, journal = {Journal of Cell Biology}, keywords = {Cell Biology}, number = {2}, pages = {433--444}, publisher = {Rockefeller University Press}, title = {{Visualization of long-lived proteins reveals age mosaicism within nuclei of postmitotic cells}}, doi = {10.1083/jcb.201809123}, volume = {218}, year = {2019}, } @article{11062, abstract = {Most neurons are not replaced during an animal’s lifetime. This nondividing state is characterized by extreme longevity and age-dependent decline of key regulatory proteins. To study the lifespans of cells and proteins in adult tissues, we combined isotope labeling of mice with a hybrid imaging method (MIMS-EM). Using 15N mapping, we show that liver and pancreas are composed of cells with vastly different ages, many as old as the animal. Strikingly, we also found that a subset of fibroblasts and endothelial cells, both known for their replicative potential, are characterized by the absence of cell division during adulthood. In addition, we show that the primary cilia of beta cells and neurons contains different structural regions with vastly different lifespans. Based on these results, we propose that age mosaicism across multiple scales is a fundamental principle of adult tissue, cell, and protein complex organization.}, author = {Arrojo e Drigo, Rafael and Lev-Ram, Varda and Tyagi, Swati and Ramachandra, Ranjan and Deerinck, Thomas and Bushong, Eric and Phan, Sebastien and Orphan, Victoria and Lechene, Claude and Ellisman, Mark H. and HETZER, Martin W}, issn = {1550-4131}, journal = {Cell Metabolism}, keywords = {Cell Biology, Molecular Biology, Physiology}, number = {2}, pages = {343--351.e3}, publisher = {Elsevier}, title = {{Age mosaicism across multiple scales in adult tissues}}, doi = {10.1016/j.cmet.2019.05.010}, volume = {30}, year = {2019}, } @article{11059, abstract = {The genome is packaged and organized nonrandomly within the 3D space of the nucleus to promote efficient gene expression and to faithfully maintain silencing of heterochromatin. The genome is enclosed within the nucleus by the nuclear envelope membrane, which contains a set of proteins that actively participate in chromatin organization and gene regulation. Technological advances are providing views of genome organization at unprecedented resolution and are beginning to reveal the ways that cells co-opt the structures of the nuclear periphery for nuclear organization and gene regulation. These genome regulatory roles of proteins of the nuclear periphery have important influences on development, disease and ageing.}, author = {Buchwalter, Abigail and Kaneshiro, Jeanae M. and HETZER, Martin W}, issn = {1471-0064}, journal = {Nature Reviews Genetics}, keywords = {Genetics (clinical), Genetics, Molecular Biology}, number = {1}, pages = {39--50}, publisher = {Springer Nature}, title = {{Coaching from the sidelines: The nuclear periphery in genome regulation}}, doi = {10.1038/s41576-018-0063-5}, volume = {20}, year = {2019}, } @article{11499, abstract = {Deep optical spectroscopic surveys of galaxies provide a unique opportunity to investigate rest-frame ultra-violet (UV) emission line properties of galaxies at z ∼ 2 − 4.5. Here we combine VLT/MUSE Guaranteed Time Observations of the Hubble Deep Field South, Ultra Deep Field, COSMOS, and several quasar fields with other publicly available data from VLT/VIMOS and VLT/FORS2 to construct a catalogue of He II λ1640 emitters at z ≳ 2. The deepest areas of our MUSE pointings reach a 3σ line flux limit of 3.1 × 10−19 erg s−1 cm−2. After discarding broad-line active galactic nuclei, we find 13 He II λ1640 detections from MUSE with a median MUV = −20.1 and 21 tentative He II λ1640 detections from other public surveys. Excluding Lyα, all except two galaxies in our sample show at least one other rest-UV emission line, with C III] λ1907, λ1909 being the most prominent. We use multi-wavelength data available in the Hubble legacy fields to derive basic galaxy properties of our sample through spectral energy distribution fitting techniques. Taking advantage of the high-quality spectra obtained by MUSE (∼10 − 30 h of exposure time per pointing), we use photo-ionisation models to study the rest-UV emission line diagnostics of the He II λ1640 emitters. Line ratios of our sample can be reproduced by moderately sub-solar photo-ionisation models, however, we find that including effects of binary stars lead to degeneracies in most free parameters. Even after considering extra ionising photons produced by extreme sub-solar metallicity binary stellar models, photo-ionisation models are unable to reproduce rest-frame He II λ1640 equivalent widths (∼0.2 − 10 Å), thus additional mechanisms are necessary in models to match the observed He II λ1640 properties.}, author = {Nanayakkara, Themiya and Brinchmann, Jarle and Boogaard, Leindert and Bouwens, Rychard and Cantalupo, Sebastiano and Feltre, Anna and Kollatschny, Wolfram and Marino, Raffaella Anna and Maseda, Michael and Matthee, Jorryt J and Paalvast, Mieke and Richard, Johan and Verhamme, Anne}, issn = {1432-0746}, journal = {Astronomy & Astrophysics}, keywords = {Space and Planetary Science, Astronomy and Astrophysics, galaxies: ISM / galaxies: star formation / galaxies: evolution / galaxies: high-redshift}, publisher = {EDP Sciences}, title = {{Exploring He II λ1640 emission line properties at z ∼2−4}}, doi = {10.1051/0004-6361/201834565}, volume = {648}, year = {2019}, } @article{11505, abstract = {Contact. This paper presents the results obtained with the Multi-Unit Spectroscopic Explorer (MUSE) at the ESO Very Large Telescope on the faint end of the Lyman-alpha luminosity function (LF) based on deep observations of four lensing clusters. The goal of our project is to set strong constraints on the relative contribution of the Lyman-alpha emitter (LAE) population to cosmic reionization. Aims. The precise aim of the present study is to further constrain the abundance of LAEs by taking advantage of the magnification provided by lensing clusters to build a blindly selected sample of galaxies which is less biased than current blank field samples in redshift and luminosity. By construction, this sample of LAEs is complementary to those built from deep blank fields, whether observed by MUSE or by other facilities, and makes it possible to determine the shape of the LF at fainter levels, as well as its evolution with redshift. Methods. We selected a sample of 156 LAEs with redshifts between 2.9 ≤ z ≤ 6.7 and magnification-corrected luminosities in the range 39 ≲ log LLyα [erg s−1] ≲43. To properly take into account the individual differences in detection conditions between the LAEs when computing the LF, including lensing configurations, and spatial and spectral morphologies, the non-parametric 1/Vmax method was adopted. The price to pay to benefit from magnification is a reduction of the effective volume of the survey, together with a more complex analysis procedure to properly determine the effective volume Vmax for each galaxy. In this paper we present a complete procedure for the determination of the LF based on IFU detections in lensing clusters. This procedure, including some new methods for masking, effective volume integration and (individual) completeness determinations, has been fully automated when possible, and it can be easily generalized to the analysis of IFU observations in blank fields. Results. As a result of this analysis, the Lyman-alpha LF has been obtained in four different redshift bins: 2.9 <  z <  6, 7, 2.9 <  z <  4.0, 4.0 <  z <  5.0, and 5.0 <  z <  6.7 with constraints down to log LLyα = 40.5. From our data only, no significant evolution of LF mean slope can be found. When performing a Schechter analysis also including data from the literature to complete the present sample towards the brightest luminosities, a steep faint end slope was measured varying from α = −1.69−0.08+0.08 to α = −1.87−0.12+0.12 between the lowest and the highest redshift bins. Conclusions. The contribution of the LAE population to the star formation rate density at z ∼ 6 is ≲50% depending on the luminosity limit considered, which is of the same order as the Lyman-break galaxy (LBG) contribution. The evolution of the LAE contribution with redshift depends on the assumed escape fraction of Lyman-alpha photons, and appears to slightly increase with increasing redshift when this fraction is conservatively set to one. Depending on the intersection between the LAE/LBG populations, the contribution of the observed galaxies to the ionizing flux may suffice to keep the universe ionized at z ∼ 6.}, author = {de La Vieuville, G. and Bina, D. and Pello, R. and Mahler, G. and Richard, J. and Drake, A. B. and Herenz, E. C. and Bauer, F. E. and Clément, B. and Lagattuta, D. and Laporte, N. and Martinez, J. and Patrício, V. and Wisotzki, L. and Zabl, J. and Bouwens, R. J. and Contini, T. and Garel, T. and Guiderdoni, B. and Marino, R. A. and Maseda, M. V. and Matthee, Jorryt J and Schaye, J. and Soucail, G.}, issn = {1432-0746}, journal = {Astronomy & Astrophysics}, keywords = {Space and Planetary Science, Astronomy and Astrophysics, gravitational lensing: strong / galaxies: high-redshift / dark ages, reionization, first stars / galaxies: clusters: general / galaxies: luminosity function, mass function}, publisher = {EDP Sciences}, title = {{Faint end of the z ∼ 3–7 luminosity function of Lyman-alpha emitters behind lensing clusters observed with MUSE}}, doi = {10.1051/0004-6361/201834471}, volume = {628}, year = {2019}, } @article{11507, abstract = {Lyman-α (Lyα) is intrinsically the brightest line emitted from active galaxies. While it originates from many physical processes, for star-forming galaxies the intrinsic Lyα luminosity is a direct tracer of the Lyman-continuum (LyC) radiation produced by the most massive O- and early-type B-stars (M⋆ ≳ 10 M⊙) with lifetimes of a few Myrs. As such, Lyα luminosity should be an excellent instantaneous star formation rate (SFR) indicator. However, its resonant nature and susceptibility to dust as a rest-frame UV photon makes Lyα very hard to interpret due to the uncertain Lyα escape fraction, fesc, Lyα. Here we explore results from the CAlibrating LYMan-α with Hα (CALYMHA) survey at z = 2.2, follow-up of Lyα emitters (LAEs) at z = 2.2 − 2.6 and a z ∼ 0−0.3 compilation of LAEs to directly measure fesc, Lyα with Hα. We derive a simple empirical relation that robustly retrieves fesc, Lyα as a function of Lyα rest-frame EW (EW0): fesc,Lyα = 0.0048 EW0[Å] ± 0.05 and we show that it constrains a well-defined anti-correlation between ionisation efficiency (ξion) and dust extinction in LAEs. Observed Lyα luminosities and EW0 are easy measurable quantities at high redshift, thus making our relation a practical tool to estimate intrinsic Lyα and LyC luminosities under well controlled and simple assumptions. Our results allow observed Lyα luminosities to be used to compute SFRs for LAEs at z ∼ 0−2.6 within ±0.2 dex of the Hα dust corrected SFRs. We apply our empirical SFR(Lyα,EW0) calibration to several sources at z ≥ 2.6 to find that star-forming LAEs have SFRs typically ranging from 0.1 to 20 M⊙ yr−1 and that our calibration might be even applicable for the most luminous LAEs within the epoch of re-ionisation. Our results imply high ionisation efficiencies (log10[ξion/Hz erg−1] = 25.4−25.6) and low dust content in LAEs across cosmic time, and will be easily tested with future observations with JWST which can obtain Hα and Hβ measurements for high-redshift LAEs.}, author = {Sobral, David and Matthee, Jorryt J}, issn = {1432-0746}, journal = {Astronomy & Astrophysics}, keywords = {Space and Planetary Science, Astronomy and Astrophysics, galaxies: high-redshift / galaxies: star formation / galaxies: statistics / galaxies: evolution / galaxies: formation / galaxies: ISM}, publisher = {EDP Sciences}, title = {{Predicting Lyα escape fractions with a simple observable: Lyα in emission as an empirically calibrated star formation rate indicator}}, doi = {10.1051/0004-6361/201833075}, volume = {623}, year = {2019}, } @article{11514, abstract = {We discuss the nature and physical properties of gas-mass selected galaxies in the ALMA spectroscopic survey (ASPECS) of the Hubble Ultra Deep Field (HUDF). We capitalize on the deep optical integral-field spectroscopy from the Multi Unit Spectroscopic Explorer (MUSE) HUDF Survey and multiwavelength data to uniquely associate all 16 line emitters, detected in the ALMA data without preselection, with rotational transitions of carbon monoxide (CO). We identify 10 as CO(2–1) at 1 < z < 2, 5 as CO(3–2) at 2 < z < 3, and 1 as CO(4–3) at z = 3.6. Using the MUSE data as a prior, we identify two additional CO(2–1) emitters, increasing the total sample size to 18. We infer metallicities consistent with (super-)solar for the CO-detected galaxies at z ≤ 1.5, motivating our choice of a Galactic conversion factor between CO luminosity and molecular gas mass for these galaxies. Using deep Chandra imaging of the HUDF, we determine an X-ray AGN fraction of 20% and 60% among the CO emitters at z ∼ 1.4 and z ∼ 2.6, respectively. Being a CO-flux-limited survey, ASPECS-LP detects molecular gas in galaxies on, above, and below the main sequence (MS) at z ∼ 1.4. For stellar masses ≥1010 (1010.5) ${M}_{\odot }$, we detect about 40% (50%) of all galaxies in the HUDF at 1 < z < 2 (2 < z < 3). The combination of ALMA and MUSE integral-field spectroscopy thus enables an unprecedented view of MS galaxies during the peak of galaxy formation.}, author = {Boogaard, Leindert A. and Decarli, Roberto and González-López, Jorge and van der Werf, Paul and Walter, Fabian and Bouwens, Rychard and Aravena, Manuel and Carilli, Chris and Bauer, Franz Erik and Brinchmann, Jarle and Contini, Thierry and Cox, Pierre and da Cunha, Elisabete and Daddi, Emanuele and Díaz-Santos, Tanio and Hodge, Jacqueline and Inami, Hanae and Ivison, Rob and Maseda, Michael and Matthee, Jorryt J and Oesch, Pascal and Popping, Gergö and Riechers, Dominik and Schaye, Joop and Schouws, Sander and Smail, Ian and Weiss, Axel and Wisotzki, Lutz and Bacon, Roland and Cortes, Paulo C. and Rix, Hans-Walter and Somerville, Rachel S. and Swinbank, Mark and Wagg, Jeff}, issn = {1538-4357}, journal = {The Astrophysical Journal}, keywords = {Space and Planetary Science, Astronomy and Astrophysics}, number = {2}, publisher = {IOP Publishing}, title = {{The ALMA spectroscopic survey in the HUDF: Nature and physical properties of gas-mass selected galaxies using MUSE spectroscopy}}, doi = {10.3847/1538-4357/ab3102}, volume = {882}, year = {2019}, }