| 1. |
- Aad, G., et al.
(författare)
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- 2013
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Tidskriftsartikel (refereegranskat)
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| 2. |
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- 2017
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Ingår i: Physical Review D. - 2470-0010 .- 2470-0029. ; 96:2
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Tidskriftsartikel (refereegranskat)
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| 3. |
- Abazov, V. M., et al.
(författare)
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Jet energy scale determination in the DO experiment
- 2014
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Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier BV. - 0168-9002 .- 1872-9576. ; 763, s. 442-475
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Tidskriftsartikel (refereegranskat)abstract
- The calibration of jet energy measured in the DO detector is presented, based on p (p) over bar collisions at a center-of-mass energy of 1.96 TeV at the Fermilab Tevatron collider, jet energies are measured using a sampling calorimeter composed of uranium and liquid argon as the passive and active media, respectively. This paper describes the energy calibration of jets performed with gamma+jet, Z+jet and dilet events, with jet transverse momentum p(T) > 6 GeV and pseudorapidity range vertical bar eta vertical bar < 3.6, The corrections are measured separately for data and simulation, achieving a precision of 1.4-1.8% for jets in the central part of the calorimeter ancl up to 3.5% for the jets with pseudorapidity vertical bar eta vertical bar = 3.0. Specific corrections are extracted to enhance the description of jet energy in simulation and in particular of the effects due to the flavor of the parton originating the jet, correcting biases up to 3-4% in jets with low PT originating from gluons and up to 6-8% in jets from b quarks. Published by Elsevier B.V.
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| 4. |
- Abazov, V. M., et al.
(författare)
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Measurement of spin correlation between top and antitop quarks produced in p(p)over-bar collisions at root s=1.96 TeV
- 2016
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Ingår i: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 757, s. 199-206
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Tidskriftsartikel (refereegranskat)abstract
- We present a measurement of the correlation between the spins of t and (t) over bar quarks produced in proton-antiproton collisions at the Tevatron Collider at a center-of-mass energy of 1.96 TeV. We apply a matrix element technique to dilepton and single-lepton+jets final states in data accumulated with the DO detector that correspond to an integrated luminosity of 9.7 fb(-1). The measured value of the correlation coefficient in the off-diagonal basis, O-off = 0.89 +/- 0.22 (stat + syst), is in agreement with the standard model prediction, and represents evidence for a top-antitop quark spin correlation difference from zero at a level of 4.2 standard deviations.
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| 5. |
- Munn-Chernoff, M. A., et al.
(författare)
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Shared genetic risk between eating disorder- and substance-use-related phenotypes: Evidence from genome-wide association studies
- 2021
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Ingår i: Addiction Biology. - : Wiley. - 1355-6215 .- 1369-1600. ; 26:1
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Tidskriftsartikel (refereegranskat)abstract
- Eating disorders and substance use disorders frequently co-occur. Twin studies reveal shared genetic variance between liabilities to eating disorders and substance use, with the strongest associations between symptoms of bulimia nervosa and problem alcohol use (genetic correlation [r(g)], twin-based = 0.23-0.53). We estimated the genetic correlation between eating disorder and substance use and disorder phenotypes using data from genome-wide association studies (GWAS). Four eating disorder phenotypes (anorexia nervosa [AN], AN with binge eating, AN without binge eating, and a bulimia nervosa factor score), and eight substance-use-related phenotypes (drinks per week, alcohol use disorder [AUD], smoking initiation, current smoking, cigarettes per day, nicotine dependence, cannabis initiation, and cannabis use disorder) from eight studies were included. Significant genetic correlations were adjusted for variants associated with major depressive disorder and schizophrenia. Total study sample sizes per phenotype ranged from similar to 2400 to similar to 537 000 individuals. We used linkage disequilibrium score regression to calculate single nucleotide polymorphism-based genetic correlations between eating disorder- and substance-use-related phenotypes. Significant positive genetic associations emerged between AUD and AN (r(g) = 0.18; false discovery rate q = 0.0006), cannabis initiation and AN (r(g) = 0.23; q < 0.0001), and cannabis initiation and AN with binge eating (r(g) = 0.27; q = 0.0016). Conversely, significant negative genetic correlations were observed between three nondiagnostic smoking phenotypes (smoking initiation, current smoking, and cigarettes per day) and AN without binge eating (r(gs) = -0.19 to -0.23; qs < 0.04). The genetic correlation between AUD and AN was no longer significant after co-varying for major depressive disorder loci. The patterns of association between eating disorder- and substance-use-related phenotypes highlights the potentially complex and substance-specific relationships among these behaviors.
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| 6. |
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| 7. |
- Tierney, W., et al.
(författare)
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A creative destruction approach to replication : Implicit work and sex morality across cultures
- 2021
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Ingår i: Journal of Experimental Social Psychology. - : Elsevier BV. - 0022-1031 .- 1096-0465. ; 93
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Tidskriftsartikel (refereegranskat)abstract
- How can we maximize what is learned from a replication study? In the creative destruction approach to replication, the original hypothesis is compared not only to the null hypothesis, but also to predictions derived from multiple alternative theoretical accounts of the phenomenon. To this end, new populations and measures are included in the design in addition to the original ones, to help determine which theory best accounts for the results across multiple key outcomes and contexts. The present pre-registered empirical project compared the Implicit Puritanism account of intuitive work and sex morality to theories positing regional, religious, and social class differences; explicit rather than implicit cultural differences in values; self-expression vs. survival values as a key cultural fault line; the general moralization of work; and false positive effects. Contradicting Implicit Puritanism's core theoretical claim of a distinct American work morality, a number of targeted findings replicated across multiple comparison cultures, whereas several failed to replicate in all samples and were identified as likely false positives. No support emerged for theories predicting regional variability and specific individual-differences moderators (religious affiliation, religiosity, and education level). Overall, the results provide evidence that work is intuitively moralized across cultures.
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| 8. |
- Adolph, C., et al.
(författare)
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Interplay among transversity induced asymmetries in hadron leptoproduction
- 2016
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Ingår i: Physics Letters B. - : Elsevier BV. - 0370-2693 .- 1873-2445. ; 753, s. 406-411
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Tidskriftsartikel (refereegranskat)abstract
- In the fragmentation of a transversely polarized quark several left-right asymmetries are possible for the hadrons in the jet. When only one unpolarized hadron is selected, it exhibits an azimuthal modulation known as the Collins effect. When a pair of oppositely charged hadrons is observed, three asymmetries can be considered, a di-hadron asymmetry and two single hadron asymmetries. In lepton deep inelastic scattering on transversely polarized nucleons all these asymmetries are coupled with the transversity distribution. From the high statistics COMPASS data on oppositely charged hadron-pair production we have investigated for the first time the dependence of these three asymmetries on the difference of the azimuthal angles of the two hadrons. The similarity of transversity induced single and di-hadron asymmetries is discussed. A new analysis of the data allows quantitative relationships to be established among them, providing for the first time strong experimental indication that the underlying fragmentation mechanisms are all driven by a common physical process.
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| 9. |
- Aguilar, J. A., et al.
(författare)
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Triboelectric backgrounds to radio-based polar ultra-high energy neutrino (UHEN) experiments
- 2023
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Ingår i: Astroparticle physics. - : Elsevier. - 0927-6505 .- 1873-2852. ; 145
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Tidskriftsartikel (refereegranskat)abstract
- In the hopes of observing the highest-energy neutrinos (E> 1 EeV) populating the Universe, both past (RICE, AURA, ANITA) and current (RNO-G, ARIANNA, ARA and TAROGE-M) polar-sited experiments exploit the impulsive radio emission produced by neutrino interactions. In such experiments, rare single event candidates must be unambiguously identified above backgrounds. Background rejection strategies to date primarily target thermal noise fluctuations and also impulsive radio-frequency signals of anthropogenic origin. In this paper, we consider the possibility that 'fake' neutrino signals may also be generated naturally via the `triboelectric effect' This broadly describes any process in which force applied at a boundary layer results in displacement of surface charge, leading to the production of an electrostatic potential difference AV. Wind blowing over granular surfaces such as snow can induce such a potential difference, with subsequent coronal discharge. Discharges over timescales as short as nanoseconds can then lead to radio-frequency emissions at characteristic MHz-GHz frequencies. Using data from various past (RICE, AURA, SATRA, ANITA) and current (RNO G, ARIANNA and ARA) neutrino experiments, we find evidence for such backgrounds, which are generally characterized by: (a) a threshold wind velocity which likely depends on the experimental trigger criteria and layout; for the experiments considered herein, this value is typically O(10 m/s), (b) frequency spectra generally shifted to the low-end of the frequency regime to which current radio experiments are typically sensitive (100-200 MHz), (c) for the strongest background signals, an apparent preference for discharges from above-surface structures, although the presence of more isotropic, lower amplitude triboelectric discharges cannot be excluded.
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| 10. |
- Aguilar, J. A., et al.
(författare)
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In situ, broadband measurement of the radio frequency attenuation length at Summit Station, Greenland
- 2022
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Ingår i: Journal of Glaciology. - : Cambridge University Press. - 0022-1430 .- 1727-5652. ; 68:272, s. 1234-1242
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Tidskriftsartikel (refereegranskat)abstract
- Over the last 25 years, radiowave detection of neutrino-generated signals, using cold polar ice as the neutrino target, has emerged as perhaps the most promising technique for detection of extragalactic ultra-high energy neutrinos (corresponding to neutrino energies in excess of 0.01 Joules, or 10(17) electron volts). During the summer of 2021 and in tandem with the initial deployment of the Radio Neutrino Observatory in Greenland (RNO-G), we conducted radioglaciological measurements at Summit Station, Greenland to refine our understanding of the ice target. We report the result of one such measurement, the radio-frequency electric field attenuation length L-alpha. We find an approximately linear dependence of L-alpha on frequency with the best fit of the average field attenuation for the upper 1500 m of ice: < L-alpha > = ((1154 +/- 121) - (0.81 +/- 0.14) (v/MHz)) m for frequencies v is an element of [145 - 3501 MHz.
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| 11. |
- Aguilar, J. A., et al.
(författare)
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Design and sensitivity of the Radio Neutrino Observatory in Greenland (RNO-G)
- 2021
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Ingår i: Journal of Instrumentation. - : Institute of Physics Publishing (IOPP). - 1748-0221. ; 16:3
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Tidskriftsartikel (refereegranskat)abstract
- This article presents the design of the Radio Neutrino Observatory Greenland (RNO-G) and discusses its scientific prospects. Using an array of radio sensors, RNO-G seeks to measure neutrinos above 10 PeV by exploiting the Askaryan effect in neutrino-induced cascades in ice. We discuss the experimental considerations that drive the design of RNO-G, present first measurements of the hardware that is to be deployed and discuss the projected sensitivity of the instrument. RNO-G will be the first production-scale radio detector for in-ice neutrino signals.
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| 12. |
- Aguilar, J. A., et al.
(författare)
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Hardware Development for the Radio Neutrino Observatory in Greenland (RNO-G)
- 2022
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Ingår i: 37th International Cosmic Ray Conference, ICRC2021. - Trieste, Italy : Proceedings of Science.
-
Konferensbidrag (refereegranskat)abstract
- The Radio Neutrino Observatory in Greenland (RNO-G) is designed to make the first observations of ultra-high energy neutrinos at energies above 10 PeV, playing a unique role in multi-messenger astrophysics as the world's largest in-ice Askaryan radio detection array. The experiment will be composed of 35 autonomous stations deployed over a 5 x 6 km grid near NSF Summit Station in Greenland. The electronics chain of each station is optimized for sensitivity and low power, incorporating 150 - 600 MHz RF antennas at both the surface and in ice boreholes, low-noise amplifiers, custom RF-over-fiber systems, and an FPGA-based phased array trigger. Each station will consume 25 W of power, allowing for a live time of 70% from a solar power system. The communications system is composed of a high-bandwidth LTE network and an ultra-low power LoRaWAN network. I will also present on the calibration and DAQ systems, as well as status of the first deployment of 10 stations in Summer 2021.
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| 13. |
- Aguilar, J. A., et al.
(författare)
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Reconstructing the neutrino energy for in-ice radio detectors
- 2022
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Ingår i: European Physical Journal C. - : Springer Nature. - 1434-6044 .- 1434-6052. ; 82:2
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Tidskriftsartikel (refereegranskat)abstract
- Since summer 2021, the Radio Neutrino Observatory in Greenland (RNO-G) is searching for astrophysical neutrinos at energies > 10 PeV by detecting the radio emission from particle showers in the ice around Summit Station, Greenland. We present an extensive simulation study that shows how RNO-G will be able to measure the energy of such particle cascades, which will in turn be used to estimate the energy of the incoming neutrino that caused them. The location of the neutrino interaction is determined using the differences in arrival times between channels and the electric field of the radio signal is reconstructed using a novel approach based on Information Field Theory. Based on these properties, the shower energy can be estimated. We show that this method can achieve an uncertainty of 13% on the logarithm of the shower energy after modest quality cuts and estimate how this can constrain the energy of the neutrino. The method presented in this paper is applicable to all similar radio neutrino detectors, such as the proposed radio array of IceCube-Gen2.
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| 14. |
- Dawson, K. S., et al.
(författare)
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An Intensive Hubble Space Telescope Survey for z>1 Type Ia Supernovae by Targeting Galaxy Clusters
- 2009
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Ingår i: Astronomical Journal. - : American Astronomical Society. - 0004-6256 .- 1538-3881. ; 138, s. 1271-1283
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Tidskriftsartikel (refereegranskat)abstract
- We present a new survey strategy to discover and study high-redshift Type Ia supernovae (SNe Ia) using the Hubble Space Telescope (HST). By targeting massive galaxy clusters at 0.9 < z < 1.5, we obtain a twofold improvement in the efficiency of finding SNe compared to an HST field survey and a factor of 3 improvement in the total yield of SN detections in relatively dust-free red-sequence galaxies. In total, sixteen SNe were discovered at z>0.95, nine of which were in galaxy clusters. This strategy provides an SN sample that can be used to decouple the effects of host-galaxy extinction and intrinsic color in high-redshift SNe, thereby reducing one of the largest systematic uncertainties in SN cosmology. Based on observations made with the NASA/ESA Hubble Space Telescope and obtained from the data archive at the Space Telescope Institute. STScI is operated by the Association of Universities for Research in Astronomy, Inc. under the NASA contract NAS 5-26555. The observations are associated with program 10496.
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| 15. |
- Sakornsakolpat, Phuwanat, et al.
(författare)
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Genetic landscape of chronic obstructive pulmonary disease identifies heterogeneous cell-type and phenotype associations
- 2019
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Ingår i: Nature Genetics. - : Springer Science and Business Media LLC. - 1061-4036 .- 1546-1718. ; 51:3, s. 494-505
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Tidskriftsartikel (refereegranskat)abstract
- Chronic obstructive pulmonary disease (COPD) is the leading cause of respiratory mortality worldwide. Genetic risk loci provide new insights into disease pathogenesis. We performed a genome-wide association study in 35,735 cases and 222,076 controls from the UK Biobank and additional studies from the International COPD Genetics Consortium. We identified 82 loci associated with P < 5 x 10-8; 47 of these were previously described in association with either COPD or population-based measures of lung function. Of the remaining 35 new loci, 13 were associated with lung function in 79,055 individuals from the SpiroMeta consortium. Using gene expression and regulation data, we identified functional enrichment of COPD risk loci in lung tissue, smooth muscle, and several lung cell types. We found 14 COPD loci shared with either asthma or pulmonary fibrosis. COPD genetic risk loci clustered into groups based on associations with quantitative imaging features and comorbidities. Our analyses provide further support for the genetic susceptibility and heterogeneity of COPD.
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| 16. |
- Suzuki, N., et al.
(författare)
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THE HUBBLE SPACE TELESCOPE CLUSTER SUPERNOVA SURVEY. V. IMPROVING THE DARK- ENERGY CONSTRAINTS ABOVE z > 1 AND BUILDING AN EARLY-TYPE-HOSTED SUPERNOVA SAMPLE
- 2012
-
Ingår i: Astrophysical Journal. - 0004-637X .- 1538-4357. ; 746:1
-
Tidskriftsartikel (refereegranskat)abstract
- We present Advanced Camera for Surveys, NICMOS, and Keck adaptive-optics-assisted photometry of 20 Type Ia supernovae (SNe Ia) from the Hubble Space Telescope (HST) Cluster Supernova Survey. The SNe Ia were discovered over the redshift interval 0.623 < z < 1.415. Of these SNe Ia, 14 pass our strict selection cuts and are used in combination with the world's sample of SNe Ia to derive the best current constraints on dark energy. Of our new SNe Ia, 10 are beyond redshift z = 1, thereby nearly doubling the statistical weight of HST-discovered SNe Ia beyond this redshift. Our detailed analysis corrects for the recently identified correlation between SN Ia luminosity and host galaxy mass and corrects the NICMOS zero point at the count rates appropriate for very distant SNe Ia. Adding these SNe improves the best combined constraint on dark-energy density,rho(DE)(z), at redshifts 1.0 < z < 1.6 by 18% (including systematic errors). For a flat. CDM universe, we find Omega(A) = 0.729 +/- 0.014 (68% confidence level (CL) including systematic errors). For a flat wCDM model, we measure a constant dark-energy equation-of-state parameter w = -1.013(-0.073)(+0.068) (68% CL). Curvature is constrained to similar to 0.7% in the owCDM model and to similar to 2% in a model in which dark energy is allowed to vary with parameters w(0) and w(a). Further tightening the constraints on the time evolution of dark energy will require several improvements, including high-quality multi-passband photometry of a sample of several dozenz > 1 SNe Ia. We describe how such a sample could be efficiently obtained by targeting cluster fields with WFC3 on board HST. The updated supernova Union2.1 compilation of 580 SNe is available at http://supernova.lbl.gov/Union.
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| 17. |
- Abazajian, Kevork, et al.
(författare)
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CMB-S4 : Forecasting Constraints on Primordial Gravitational Waves
- 2022
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Ingår i: Astrophysical Journal. - : American Astronomical Society. - 0004-637X .- 1538-4357. ; 926:1
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Tidskriftsartikel (refereegranskat)abstract
- CMB-S4—the next-generation ground-based cosmic microwave background (CMB) experiment—is set to significantly advance the sensitivity of CMB measurements and enhance our understanding of the origin and evolution of the universe. Among the science cases pursued with CMB-S4, the quest for detecting primordial gravitational waves is a central driver of the experimental design. This work details the development of a forecasting framework that includes a power-spectrum-based semianalytic projection tool, targeted explicitly toward optimizing constraints on the tensor-to-scalar ratio, r, in the presence of Galactic foregrounds and gravitational lensing of the CMB. This framework is unique in its direct use of information from the achieved performance of current Stage 2–3 CMB experiments to robustly forecast the science reach of upcoming CMB-polarization endeavors. The methodology allows for rapid iteration over experimental configurations and offers a flexible way to optimize the design of future experiments, given a desired scientific goal. To form a closed-loop process, we couple this semianalytic tool with map-based validation studies, which allow for the injection of additional complexity and verification of our forecasts with several independent analysis methods. We document multiple rounds of forecasts for CMB-S4 using this process and the resulting establishment of the current reference design of the primordial gravitational-wave component of the Stage-4 experiment, optimized to achieve our science goals of detecting primordial gravitational waves for r > 0.003 at greater than 5σ, or in the absence of a detection, of reaching an upper limit of r < 0.001 at 95% CL.
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| 18. |
- Bhat, N. D. R., et al.
(författare)
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Observations of Low-frequency Radio Emission from Millisecond Pulsars and Multipath Propagation in the Interstellar Medium
- 2018
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Ingår i: Astrophysical Journal, Supplement Series. - : American Astronomical Society. - 1538-4365 .- 0067-0049. ; 238:1
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Tidskriftsartikel (refereegranskat)abstract
- Studying the gravitational-wave sky with pulsar timing arrays (PTAs) is a key science goal for the Square Kilometre Array (SKA) and its pathfinder telescopes. With current PTAs reaching sub-microsecond timing precision, making accurate measurements of interstellar propagation effects and mitigating them effectively has become increasingly important to realize PTA goals. As these effects are much stronger at longer wavelengths, low-frequency observations are most appealing for characterizing the interstellar medium (ISM) along the sight lines toward PTA pulsars. The Murchison Widefield Array (MWA) and the Engineering Development Array (EDA), which utilizes MWA technologies, present promising opportunities for undertaking such studies, particularly for PTA pulsars located in the southern sky. Such pulsars are also the prime targets for PTA efforts planned with the South African MeerKAT, and eventually with the SKA. In this paper we report on observations of two bright southern millisecond pulsars, PSR J0437-4715 and PSR J2145-0750, made with these facilities; MWA observations sampled multiple frequencies across the 80-250 MHz frequency range, while the EDA provided direct-sampled baseband data to yield a large instantaneous usable bandwidth of similar to 200 MHz. Using these exploratory observations, we investigate various aspects relating to pulsar emission and ISM properties, such as spectral evolution of the mean pulse shape, scintillation as a function of frequency, chromaticity in interstellar dispersion, and flux density spectra at low frequencies. Systematic and regular monitoring observations will help ascertain the role of low-frequency measurements in PTA experiments, while simultaneously providing a detailed characterization of the ISM toward the pulsars, which will be useful in devising optimal observing strategies for future PTA experiments.
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| 19. |
- Duggan, D., et al.
(författare)
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Two genome-wide association studies of aggressive prostate cancer implicate putative prostate tumor suppressor gene DAB2IP
- 2007
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Ingår i: Journal of the National Cancer Institute. - : Oxford University Press (OUP). - 0027-8874 .- 1460-2105. ; 99:24, s. 1836-1844
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Tidskriftsartikel (refereegranskat)abstract
- Background: The consistent finding of a genetic susceptibility to prostate cancer suggests that there are germline sequence variants predisposing individuals to this disease. These variants could be useful in screening and treatment. Methods: We performed an exploratory genome-wide association scan in 498 men with aggressive prostate cancer and 494 control subjects selected from a population-based case-control study in Sweden. We combined the results of this scan with those for aggressive prostate cancer from the publicly available Cancer Genetic Markers of Susceptibility (CGEMS) Study. Single-nucleotide polymorphisms (SNPs) that showed statistically significant associations with the risk of aggressive prostate cancer based on two-sided allele tests were tested for their association with aggressive prostate cancer in two independent study populations composed of individuals of European or African American descent using one-sided tests and the genetic model (dominant or additive) associated with the lowest value in the exploratory study. Results: Among the approximately 60000 SNPs that were common to our study and CGEMS, we identified seven that had a similar (positive or negative) and statistically significant (P<.01) association with the risk of aggressive prostate cancer in both studies. Analysis of the distribution of these SNPs among 1032 prostate cancer patients and 571 control subjects of European descent indicated that one, rs1571801, located in the DAB2IP gene, which encodes a novel Ras GTPase-activating protein and putative prostate tumor suppressor, was associated with aggressive prostate cancer (one-sided P value =. 004). The association was also statistically significant in an African American study population that included 210 prostate cancer patients and 346 control subjects (one-sided P value =. 02). Conclusion: A genetic variant in DAB2IP may be associated with the risk of aggressive prostate cancer and should be evaluated further.
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| 20. |
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| 21. |
- Shrine, Nick, et al.
(författare)
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New genetic signals for lung function highlight pathways and chronic obstructive pulmonary disease associations across multiple ancestries
- 2019
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Ingår i: Nature Genetics. - : Springer Science and Business Media LLC. - 1061-4036 .- 1546-1718. ; 51:3, s. 481-493
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Tidskriftsartikel (refereegranskat)abstract
- Reduced lung function predicts mortality and is key to the diagnosis of chronic obstructive pulmonary disease (COPD). In a genome-wide association study in 400,102 individuals of European ancestry, we define 279 lung function signals, 139 of which are new. In combination, these variants strongly predict COPD in independent populations. Furthermore, the combined effect of these variants showed generalizability across smokers and never smokers, and across ancestral groups. We highlight biological pathways, known and potential drug targets for COPD and, in phenome-wide association studies, autoimmune-related and other pleiotropic effects of lung function-associated variants. This new genetic evidence has potential to improve future preventive and therapeutic strategies for COPD.
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| 22. |
- Ade, Peter, et al.
(författare)
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The Simons Observatory : science goals and forecasts
- 2019
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Ingår i: Journal of Cosmology and Astroparticle Physics. - : IOP Publishing. - 1475-7516. ; :2
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Tidskriftsartikel (refereegranskat)abstract
- The Simons Observatory (SO) is a new cosmic microwave background experiment being built on Cerro Toco in Chile, due to begin observations in the early 2020s. We describe the scientific goals of the experiment, motivate the design, and forecast its performance. SO will measure the temperature and polarization anisotropy of the cosmic microwave background in six frequency bands centered at: 27, 39, 93, 145, 225 and 280 GHz. The initial con figuration of SO will have three small-aperture 0.5-m telescopes and one large-aperture 6-m telescope, with a total of 60,000 cryogenic bolometers. Our key science goals are to characterize the primordial perturbations, measure the number of relativistic species and the mass of neutrinos, test for deviations from a cosmological constant, improve our understanding of galaxy evolution, and constrain the duration of reionization. The small aperture telescopes will target the largest angular scales observable from Chile, mapping approximate to 10% of the sky to a white noise level of 2 mu K-arcmin in combined 93 and 145 GHz bands, to measure the primordial tensor-to-scalar ratio, r, at a target level of sigma(r) = 0.003. The large aperture telescope will map approximate to 40% of the sky at arcminute angular resolution to an expected white noise level of 6 mu K-arcmin in combined 93 and 145 GHz bands, overlapping with the majority of the Large Synoptic Survey Telescope sky region and partially with the Dark Energy Spectroscopic Instrument. With up to an order of magnitude lower polarization noise than maps from the Planck satellite, the high-resolution sky maps will constrain cosmological parameters derived from the damping tail, gravitational lensing of the microwave background, the primordial bispectrum, and the thermal and kinematic Sunyaev-Zel'dovich effects, and will aid in delensing the large-angle polarization signal to measure the tensor-to-scalar ratio. The survey will also provide a legacy catalog of 16,000 galaxy clusters and more than 20,000 extragalactic sources.
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| 23. |
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| 24. |
- Barbary, K., et al.
(författare)
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THE HUBBLE SPACE TELESCOPE CLUSTER SUPERNOVA SURVEY. II. THE TYPE Ia SUPERNOVA RATE IN HIGH-REDSHIFT GALAXY CLUSTERS
- 2012
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Ingår i: Astrophysical Journal. - 0004-637X .- 1538-4357. ; 745:1, s. 32-
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Tidskriftsartikel (refereegranskat)abstract
- We report a measurement of the Type Ia supernova (SN Ia) rate in galaxy clusters at 0.9 < z < 1.46 from the Hubble Space Telescope Cluster Supernova Survey. This is the first cluster SN Ia rate measurement with detected z > 0.9 SNe. Finding 8 +/- 1 cluster SNe Ia, we determine an SN Ia rate of 0.50(-0.19)(+0.23) (stat) (+0.10)(-0.09) (sys) h(70)(2) SNuB (SNuB equivalent to 10(-12) SNe (L-1)circle dot(,B) yr(-1)). In units of stellar mass, this translates to 0.36(-0.13)(+0.16) (stat) (+0.07)(-0.06) (sys) h(70)(2) SNuM (SNuM = 10(-12) SNe M-1 circle dot yr(-1)). This represents a factor of approximate to 5 +/- 2 increase over measurements of the cluster rate at z < 0.2. We parameterize the late-time SN Ia delay time distribution (DTD) with a power law: Psi(t) t(s). Under the approximation of a single-burst cluster formation redshift of z(f) = 3, our rate measurement in combination with lower-redshift cluster SN Ia rates constrains s = -1.41(-0.40)(+0.47), consistent with measurements of the DTD in the field. This measurement is generally consistent with expectations for the double degenerate scenario and inconsistent with some models for the single degenerate scenario predicting a steeper DTD at large delay times. We check for environmental dependence and the influence of younger stellar populations by calculating the rate specifically in cluster red-sequence galaxies and in morphologically early-type galaxies, finding results similar to the full cluster rate. Finally, the upper limit of one hostless cluster SN Ia detected in the survey implies that the fraction of stars in the intra-cluster medium is less than 0.47 (95% confidence), consistent with measurements at lower redshifts.
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| 25. |
- Barbary, K., et al.
(författare)
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THE HUBBLE SPACE TELESCOPE CLUSTER SUPERNOVA SURVEY. VI. THE VOLUMETRIC TYPE Ia SUPERNOVA RATE
- 2012
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Ingår i: Astrophysical Journal. - 0004-637X .- 1538-4357. ; 745:1
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Tidskriftsartikel (refereegranskat)abstract
- We present a measurement of the volumetric Type Ia supernova (SN Ia) rate out to z similar or equal to 1.6 from the Hubble Space Telescope Cluster Supernova Survey. In observations spanning 189 orbits with the Advanced Camera for Surveys we discovered 29 SNe, of which approximately 20 are SNe Ia. Twelve of these SNe Ia are located in the foregrounds and backgrounds of the clusters targeted in the survey. Using these new data, we derive the volumetric SN Ia rate in four broad redshift bins, finding results consistent with previous measurements at z greater than or similar to 1 and strengthening the case for an SN Ia rate that is greater than or similar to 0.6 x 10(-4) h(70)(3) yr(-1) Mpc(-3) at z similar to 1 and flattening out at higher redshift. We provide SN candidates and efficiency calculations in a form that makes it easy to rebin and combine these results with other measurements for increased statistics. Finally, we compare the assumptions about host-galaxy dust extinction used in different high-redshift rate measurements, finding that different assumptions may induce significant systematic differences between measurements.
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| 26. |
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| 27. |
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| 28. |
- Amanullah, Rahman, et al.
(författare)
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Spectra and Hubble Space Telescope Light Curves of Six Type Ia Supernovae at 0.511 < z < 1.12 and the Union2 Compilation
- 2010
-
Ingår i: Astrophysical Journal. - 0004-637X .- 1538-4357. ; 716, s. 712-738
-
Tidskriftsartikel (refereegranskat)abstract
- We report on work to increase the number of well-measured Type Ia supernovae (SNe Ia) at high redshifts. Light curves, including high signal-to-noise Hubble Space Telescope data, and spectra of six SNe Ia that were discovered during 2001, are presented. Additionally, for the two SNe with z > 1, we present ground-based J-band photometry from Gemini and the Very Large Telescope. These are among the most distant SNe Ia for which ground-based near-IR observations have been obtained. We add these six SNe Ia together with other data sets that have recently become available in the literature to the Union compilation. We have made a number of refinements to the Union analysis chain, the most important ones being the refitting of all light curves with the SALT2 fitter and an improved handling of systematic errors. We call this new compilation, consisting of 557 SNe, the Union2 compilation. The flat concordance ΛCDM model remains an excellent fit to the Union2 data with the best-fit constant equation-of-state parameter w = -0.997+0.050 -0.054(stat)+0.077 -0.082(stat + sys together) for a flat universe, or w = -1.038+0.056 -0.059(stat)+0.093 -0.097(stat + sys together) with curvature. We also present improved constraints on w(z). While no significant change in w with redshift is detected, there is still considerable room for evolution in w. The strength of the constraints depends strongly on redshift. In particular, at z >~ 1, the existence and nature of dark energy are only weakly constrained by the data. Based in part on observations made with the NASA/ESA Hubble Space Telescope, obtained from the data archive at the Space Telescope Science Institute (STScI). STScI is operated by the Association of Universities for Research in Astronomy (AURA), Inc. under the NASA contract NAS 5-26555. The observations are associated with programs HST-GO-08585 and HST-GO-09075. Based, in part, on observations obtained at the ESO La Silla Paranal Observatory (ESO programs 67.A-0361 and 169.A-0382). Based, in part, on observations obtained at the Cerro-Tololo Inter-American Observatory (CTIO), National Optical Astronomy Observatory (NOAO). Based on observations obtained at the Canada-France-Hawaii Telescope (CFHT). Based, in part, on observations obtained at the Gemini Observatory (Gemini programs GN-2001A-SV-19 and GN-2002A-Q-31). Based, in part on observations obtained at the Subaru Telescope. Based, in part, on data that were obtained at the W. M. Keck Observatory.
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| 29. |
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| 30. |
- Haas, Brian J., et al.
(författare)
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Genome sequence and analysis of the Irish potato famine pathogen Phytophthora infestans
- 2009
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 461:7262, s. 393-398
-
Tidskriftsartikel (refereegranskat)abstract
- Phytophthora infestans is the most destructive pathogen of potato and a model organism for the oomycetes, a distinct lineage of fungus-like eukaryotes that are related to organisms such as brown algae and diatoms. As the agent of the Irish potato famine in the mid-nineteenth century, P. infestans has had a tremendous effect on human history, resulting in famine and population displacement(1). To this day, it affects world agriculture by causing the most destructive disease of potato, the fourth largest food crop and a critical alternative to the major cereal crops for feeding the world's population(1). Current annual worldwide potato crop losses due to late blight are conservatively estimated at $6.7 billion(2). Management of this devastating pathogen is challenged by its remarkable speed of adaptation to control strategies such as genetically resistant cultivars(3,4). Here we report the sequence of the P. infestans genome, which at similar to 240 megabases (Mb) is by far the largest and most complex genome sequenced so far in the chromalveolates. Its expansion results from a proliferation of repetitive DNA accounting for similar to 74% of the genome. Comparison with two other Phytophthora genomes showed rapid turnover and extensive expansion of specific families of secreted disease effector proteins, including many genes that are induced during infection or are predicted to have activities that alter host physiology. These fast-evolving effector genes are localized to highly dynamic and expanded regions of the P. infestans genome. This probably plays a crucial part in the rapid adaptability of the pathogen to host plants and underpins its evolutionary potential.
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| 31. |
- Huang, X., et al.
(författare)
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HUBBLE SPACE TELESCOPE DISCOVERY OF A z=3.9 MULTIPLY IMAGED GALAXY BEHIND THE COMPLEX CLUSTER LENS WARPS J1415.1+36 AT z=1.026
- 2009
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Ingår i: ASTROPHYS J LETT. ; 707:1, s. l12-L16
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Tidskriftsartikel (refereegranskat)abstract
- We report the discovery of a multiply lensed Ly alpha emitter at z = 3.90 behind the massive cluster WARPS J1415.1+3612 at z = 1.026. Images taken by the Hubble Space Telescope using the Advanced Camera for Surveys reveal a complex lensing system that produces a prominent, highly magnified arc and a triplet of smaller arcs grouped tightly around a spectroscopically confirmed cluster member. Spectroscopic observations using the Faint Object Camera and Spectrograph on Subaru confirm strong Lya emission in the source galaxy and provide the redshifts for more than 21 cluster members with a velocity dispersion of 807 +/- 185 km s(-1). Assuming a singular isothermal sphere profile, the mass within the Einstein ring (7.13 +/- 0.'' 38) corresponds to a central velocity dispersion of 686(-19)(+15) km s(-1) for the cluster, consistent with the value estimated from cluster member redshifts. Our mass profile estimate from combining strong lensing and dynamical analyses is in good agreement with both X-ray and weak lensing results.
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| 32. |
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| 33. |
- Rubin, D., et al.
(författare)
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A CALIBRATION OF NICMOS CAMERA 2 FOR LOW COUNT RATES
- 2015
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Ingår i: Astronomical Journal. - : American Astronomical Society. - 0004-6256 .- 1538-3881. ; 149:5
-
Tidskriftsartikel (refereegranskat)abstract
- NICMOS 2 observations are crucial for constraining distances to most of the existing sample of z > 1 SNe Ia. Unlike conventional calibration programs, these observations involve long exposure times and low count rates. Reciprocity failure is known to exist in HgCdTe devices and a correction for this effect has already been implemented for high and medium count rates. However, observations at faint count rates rely on extrapolations. Here instead, we provide a new zero-point calibration directly applicable to faint sources. This is obtained via inter-calibration of NIC2 F110W/F160W with the Wide Field Camera 3 (WFC3) in the low count-rate regime using z similar to 1 elliptical galaxies as tertiary calibrators. These objects have relatively simple near-IR spectral energy distributions, uniform colors, and their extended nature gives a superior signal-to-noise ratio at the same count rate than would stars. The use of extended objects also allows greater tolerances on point-spread function profiles. We find space telescope magnitude zero points (after the installation of the NICMOS cooling system, NCS) of 25.296 +/- 0.022 for F110W and 25.803 +/- 0.023 for F160W, both in agreement with the calibration extrapolated from count rates greater than or similar to 1000 times larger (25.262 and 25.799). Before the installation of the NCS, we find 24.843 +/- 0.025 for F110W and 25.498 +/- 0.021 for F160W, also in agreement with the high-count-rate calibration (24.815 and 25.470). We also check the standard bandpasses of WFC3 and NICMOS 2 using a range of stars and galaxies at different colors and find mild tension for WFC3, limiting the accuracy of the zero points. To avoid human bias, our cross-calibration was blinded in that the fitted zero-point differences were hidden until the analysis was finalized.
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| 34. |
- Yi, Chuixiang, et al.
(författare)
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Climate control of terrestrial carbon exchange across biomes and continents
- 2010
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Ingår i: Environmental Research Letters. - : IOP Publishing. - 1748-9326. ; 5:3
-
Tidskriftsartikel (refereegranskat)abstract
- Understanding the relationships between climate and carbon exchange by terrestrial ecosystems is critical to predict future levels of atmospheric carbon dioxide because of the potential accelerating effects of positive climate-carbon cycle feedbacks. However, directly observed relationships between climate and terrestrial CO2 exchange with the atmosphere across biomes and continents are lacking. Here we present data describing the relationships between net ecosystem exchange of carbon (NEE) and climate factors as measured using the eddy covariance method at 125 unique sites in various ecosystems over six continents with a total of 559 site-years. We find that NEE observed at eddy covariance sites is (1) a strong function of mean annual temperature at mid-and high-latitudes, (2) a strong function of dryness at mid-and low-latitudes, and (3) a function of both temperature and dryness around the mid-latitudinal belt (45 degrees N). The sensitivity of NEE to mean annual temperature breaks down at similar to 16 degrees C (a threshold value of mean annual temperature), above which no further increase of CO2 uptake with temperature was observed and dryness influence overrules temperature influence.
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| 35. |
- Andersson, L., et al.
(författare)
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The Langmuir Probe and Waves (LPW) Instrument for MAVEN
- 2015
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Ingår i: Space Science Reviews. - : Springer Science and Business Media LLC. - 0038-6308 .- 1572-9672. ; 195:1-4, s. 173-198
-
Forskningsöversikt (refereegranskat)abstract
- We describe the sensors, the sensor biasing and control, the signal-processing unit, and the operation of the Langmuir Probe and Waves (LPW) instrument on the Mars Atmosphere and Volatile EvolutioN (MAVEN) mission. The LPW instrument is designed to measure the electron density and temperature in the ionosphere of Mars and to measure spectral power density of waves (DC-2 MHz) in Mars' ionosphere, including one component of the electric field. Low-frequency plasma waves can heat ions resulting in atmospheric loss. Higher-frequency waves are used to calibrate the density measurement and to study strong plasma processes. The LPW is part of the Particle and Fields (PF) suite on the MAVEN spacecraft. The LPW instrument utilizes two, 40 cm long by 0.635 cm diameter cylindrical sensors with preamplifiers, which can be configured to measure either plasma currents or plasma waves. The sensors are mounted on a pair of meter long stacer booms. The sensors and nearby surfaces are controlled by a Boom Electronics Board (BEB). The Digital Fields Board (DFB) conditions the analog signals, converts the analog signals to digital, processes the digital signals including spectral analysis, and packetizes the data for transmission. The BEB and DFB are located inside of the Particle and Fields Digital Processing Unit (PFDPU).
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| 36. |
- Anker, A., et al.
(författare)
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Probing the angular and polarization reconstruction of the ARIANNA detector at the South Pole
- 2020
-
Ingår i: Journal of Instrumentation. - : IOP PUBLISHING LTD. - 1748-0221. ; 15:9
-
Tidskriftsartikel (refereegranskat)abstract
- The sources of ultra-high energy (UHE) cosmic rays, which can have energies up to 10(20) eV, remain a mystery. UHE neutrinos may provide important clues to understanding the nature of cosmic-ray sources. ARIANNA aims to detect UHE neutrinos via radio (Askaryan) emission from particle showers when a neutrino interacts with ice, which is an efficient method for neutrinos with energies between 10(16) eV and 10(20) eV. The ARIANNA radio detectors are located in Antarctic ice just beneath the surface. Neutrino observation requires that radio pulses propagate to the antennas at the surface with minimum distortion by the ice and firn medium. Using the residual hole from the South Pole Ice Core Project, radio pulses were emitted from a transmitter located up to 1.7 km below the snow surface. By measuring these signals with an ARIANNA surface station, the angular and polarization reconstruction abilities are quantified, which are required to measure the direction of the neutrino. After deconvolving the raw signals for the detector response and attenuation from propagation through the ice, the signal pulses show no significant distortion and agree with a reference measurement of the emitter made in an anechoic chamber. Furthermore, the signal pulses reveal no significant birefringence for our tested geometry of mostly vertical ice propagation. The origin of the transmitted radio pulse was measured with an angular resolution of 0.37 degrees indicating that the neutrino direction can be determined with good precision if the polarization of the radio-pulse can be well determined. In the present study we obtained a resolution of the polarization vector of 2.7 degrees. Neither measurement show a significant offset relative to expectation.
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| 37. |
- Austin, CC, et al.
(författare)
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Fostering global data sharing: highlighting the recommendations of the Research Data Alliance COVID-19 working group
- 2020
-
Ingår i: Wellcome open research. - : F1000 Research Ltd. - 2398-502X. ; 5, s. 267-
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Tidskriftsartikel (refereegranskat)abstract
- The systemic challenges of the COVID-19 pandemic require cross-disciplinary collaboration in a global and timely fashion. Such collaboration needs open research practices and the sharing of research outputs, such as data and code, thereby facilitating research and research reproducibility and timely collaboration beyond borders. The Research Data Alliance COVID-19 Working Group recently published a set of recommendations and guidelines on data sharing and related best practices for COVID-19 research. These guidelines include recommendations for clinicians, researchers, policy- and decision-makers, funders, publishers, public health experts, disaster preparedness and response experts, infrastructure providers from the perspective of different domains (Clinical Medicine, Omics, Epidemiology, Social Sciences, Community Participation, Indigenous Peoples, Research Software, Legal and Ethical Considerations), and other potential users. These guidelines include recommendations for researchers, policymakers, funders, publishers and infrastructure providers from the perspective of different domains (Clinical Medicine, Omics, Epidemiology, Social Sciences, Community Participation, Indigenous Peoples, Research Software, Legal and Ethical Considerations). Several overarching themes have emerged from this document such as the need to balance the creation of data adherent to FAIR principles (findable, accessible, interoperable and reusable), with the need for quick data release; the use of trustworthy research data repositories; the use of well-annotated data with meaningful metadata; and practices of documenting methods and software. The resulting document marks an unprecedented cross-disciplinary, cross-sectoral, and cross-jurisdictional effort authored by over 160 experts from around the globe. This letter summarises key points of the Recommendations and Guidelines, highlights the relevant findings, shines a spotlight on the process, and suggests how these developments can be leveraged by the wider scientific community.
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| 38. |
- Barbary, K., et al.
(författare)
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Discovery of an Unusual Optical Transient with the Hubble Space Telescope
- 2009
-
Ingår i: Astrophysical Journal. - 0004-637X .- 1538-4357. ; 690, s. 1358-1362
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Tidskriftsartikel (refereegranskat)abstract
- We present observations of SCP 06F6, an unusual optical transient discovered during the Hubble Space Telescope Cluster Supernova Survey. The transient brightened over a period of ~100 days, reached a peak magnitude of ~ 21.0 in both i 775 and z 850, and then declined over a similar timescale. There is no host galaxy or progenitor star detected at the location of the transient to a 3σ upper limit of i 775 >= 26.4 and z 850 >= 26.1, giving a corresponding lower limit on the flux increase of a factor of ~ 120. Multiple spectra show five broad absorption bands between 4100 Å and 6500 Å, and a mostly featureless continuum longward of 6500 Å. The shape of the light curve is inconsistent with microlensing. The transient's spectrum, in addition to being inconsistent with all known supernova types, does not match any spectrum in the Sloan Digital Sky Survey database. We suggest that the transient may be one of a new class. Based in part on observations made with the NASA/ESA Hubble Space Telescope, obtained from the data archive at the Space Telescope Science Institute (STScI). STScI is operated by the Association of Universities for Research in Astronomy (AURA), Inc. under the NASA contract NAS 5-26555. The observations are associated with program GO-10496. Based in part on observations obtained at the European Southern Observatory under ESO program 077.A-0110. Based in part on observations collected at Subaru Telescope, which is operated by the National Astronomical Observatory of Japan. Some of the data presented herein were obtained at the W.M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California, and NASA.
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| 39. |
- Bigdeli, TB, et al.
(författare)
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Contributions of common genetic variants to risk of schizophrenia among individuals of African and Latino ancestry
- 2020
-
Ingår i: Molecular psychiatry. - : Springer Science and Business Media LLC. - 1476-5578 .- 1359-4184. ; 25:10, s. 2455-2467
-
Tidskriftsartikel (refereegranskat)abstract
- Schizophrenia is a common, chronic and debilitating neuropsychiatric syndrome affecting tens of millions of individuals worldwide. While rare genetic variants play a role in the etiology of schizophrenia, most of the currently explained liability is within common variation, suggesting that variation predating the human diaspora out of Africa harbors a large fraction of the common variant attributable heritability. However, common variant association studies in schizophrenia have concentrated mainly on cohorts of European descent. We describe genome-wide association studies of 6152 cases and 3918 controls of admixed African ancestry, and of 1234 cases and 3090 controls of Latino ancestry, representing the largest such study in these populations to date. Combining results from the samples with African ancestry with summary statistics from the Psychiatric Genomics Consortium (PGC) study of schizophrenia yielded seven newly genome-wide significant loci, and we identified an additional eight loci by incorporating the results from samples with Latino ancestry. Leveraging population differences in patterns of linkage disequilibrium, we achieve improved fine-mapping resolution at 22 previously reported and 4 newly significant loci. Polygenic risk score profiling revealed improved prediction based on trans-ancestry meta-analysis results for admixed African (Nagelkerke’s R2 = 0.032; liability R2 = 0.017; P < 10−52), Latino (Nagelkerke’s R2 = 0.089; liability R2 = 0.021; P < 10−58), and European individuals (Nagelkerke’s R2 = 0.089; liability R2 = 0.037; P < 10−113), further highlighting the advantages of incorporating data from diverse human populations.
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| 40. |
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| 41. |
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| 42. |
- Gleason, J. D., et al.
(författare)
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Sources and cycling of mercury in the paleo Arctic Ocean from Hg stable isotope variations in Eocene and Quaternary sediments
- 2017
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Ingår i: Geochimica et Cosmochimica Acta. - : Elsevier BV. - 0016-7037 .- 1872-9533. ; 197, s. 245-262
-
Tidskriftsartikel (refereegranskat)abstract
- Mercury stable isotopic compositions were determined for marine sediments from eight locations in the Arctic Ocean Basin. Mass dependent fractionation (MDF) and mass independent fractionation (MIF) of Hg stable isotopes were recorded across a variety of depositional environments, water depths, and stratigraphic ages. delta(202) Hg (MDF) ranges from -2.34% to -0.78%; Delta(199) Hg (MIF) from -0.18% to +0.12%; and Delta(201) Hg (MIF) from -0.29% to + 0.05% for the complete data set (n = 33). Holocene sediments from the Chukchi Sea and Morris Jesup Rise record the most negative Delta(199) Hg values, while Pleistocene sediments from the Central Arctic Ocean record the most positive Delta(199) Hg values. The most negative delta(202) Hg values are recorded in Pleistocene sediments. Eocene sediments (Lomonosov Ridge) show some overlap in their Hg isotopic compositions with Quaternary sediments, with a sample of the Arctic Ocean PETM (56 Ma) most closely matching the average Hg isotopic composition of Holocene Arctic marine sediments. Collectively, these data support a terrestrially-dominated Hg source input for Arctic Ocean sediment through time, although other sources, as well as influences of sea ice, atmospheric mercury depletion events (AMDEs), and anthropogenic Hg (in core top samples) on Hg isotopic signatures must also be considered.
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| 43. |
- Jang, Seon-Kyeong, et al.
(författare)
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Rare genetic variants explain missing heritability in smoking.
- 2022
-
Ingår i: Nature human behaviour. - : Springer Science and Business Media LLC. - 2397-3374. ; 6:11, s. 1577-1586
-
Tidskriftsartikel (refereegranskat)abstract
- Common genetic variants explain less variation in complex phenotypes than inferred from family-based studies, and there is a debate on the source of this 'missing heritability'. We investigated the contribution of rare genetic variants to tobacco use with whole-genome sequences from up to 26,257 unrelated individuals of European ancestries and 11,743 individuals of African ancestries. Across four smoking traits, single-nucleotide-polymorphism-based heritability ([Formula: see text]) was estimated from 0.13 to 0.28 (s.e., 0.10-0.13) in European ancestries, with 35-74% of it attributable to rare variants with minor allele frequencies between 0.01% and 1%. These heritability estimates are 1.5-4 times higher than past estimates based on common variants alone and accounted for 60% to 100% of our pedigree-based estimates of narrow-sense heritability ([Formula: see text], 0.18-0.34). In the African ancestry samples, [Formula: see text] was estimated from 0.03 to 0.33 (s.e., 0.09-0.14) across the four smoking traits. These results suggest that rare variants are important contributors to the heritability of smoking.
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| 44. |
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| 45. |
- Nobili, Serena, et al.
(författare)
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Constraining Dust and Color Variations of High-z SNe Using NICMOS on the Hubble Space Telescope
- 2009
-
Ingår i: Astrophysical Journal. - 0004-637X .- 1538-4357. ; 700, s. 1415-1427
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Tidskriftsartikel (refereegranskat)abstract
- We present data from the Supernova Cosmology Project for five high redshift Type Ia supernovae (SNe Ia) that were obtained using the NICMOS infrared camera on the Hubble Space Telescope. We add two SNe from this sample to a rest-frame I-band Hubble diagram, doubling the number of high redshift supernovae on this diagram. This I-band Hubble diagram is consistent with a flat universe (ΩM, ΩΛ) = (0.29, 0.71). A homogeneous distribution of large grain dust in the intergalactic medium (replenishing dust) is incompatible with the data and is excluded at the 5σ confidence level, if the SN host galaxy reddening is corrected assuming RV = 1.75. We use both optical and infrared observations to compare photometric properties of distant SNe Ia with those of nearby objects. We find generally good agreement with the expected color evolution for all SNe except the highest redshift SN in our sample (SN 1997ek at z = 0.863) which shows a peculiar color behavior. We also present spectra obtained from ground-based telescopes for type identification and determination of redshift. Based on observations made with the NASA/ESA Hubble Space Telescope, obtained from the data archive at the Space Telescope Science Institute. STScI is operated by the association of Universities for Research in Astronomy, Inc. under the NASA contract NAS 5-26555. The observations are associated with program GO-07850.
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| 46. |
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| 47. |
- Pleunis, Z., et al.
(författare)
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LOFAR Detection of 110-188MHz emission and frequency-dependent activity from FRB20180916B
- 2021
-
Ingår i: Astrophysical Journal Letters. - : American Astronomical Society. - 2041-8213 .- 2041-8205. ; 911:1
-
Tidskriftsartikel (refereegranskat)abstract
- The object FRB 20180916B is a well-studied repeating fast radio burst source. Its proximity (∼150 Mpc), along with detailed studies of the bursts, has revealed many clues about its nature, including a 16.3 day periodicity in its activity. Here we report on the detection of 18 bursts using LOFAR at 110-188 MHz, by far the lowest-frequency detections of any FRB to date. Some bursts are seen down to the lowest observed frequency of 110 MHz, suggesting that their spectra extend even lower. These observations provide an order-of-magnitude stronger constraint on the optical depth due to freëCfree absorption in the source's local environment. The absence of circular polarization and nearly flat polarization angle curves are consistent with burst properties seen at 300-1700 MHz. Compared with higher frequencies, the larger burst widths (∼40-160 ms at 150 MHz) and lower linear polarization fractions are likely due to scattering. We find ∼2-3 rad m variations in the Faraday rotation measure that may be correlated with the activity cycle of the source. We compare the LOFAR burst arrival times to those of 38 previously published and 22 newly detected bursts from the uGMRT (200-450 MHz) and CHIME/FRB (400-800 MHz). Simultaneous observations show five CHIME/FRB bursts when no emission is detected by LOFAR. We find that the burst activity is systematically delayed toward lower frequencies by about 3 days from 600 to 150 MHz. We discuss these results in the context of a model in which FRB 20180916B is an interacting binary system featuring a neutron star and high-mass stellar companion.
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| 48. |
- Shrine, N, et al.
(författare)
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Multi-ancestry genome-wide association analyses improve resolution of genes and pathways influencing lung function and chronic obstructive pulmonary disease risk
- 2023
-
Ingår i: Nature genetics. - : Springer Science and Business Media LLC. - 1546-1718 .- 1061-4036. ; 55:3, s. 410-
-
Tidskriftsartikel (refereegranskat)abstract
- Lung-function impairment underlies chronic obstructive pulmonary disease (COPD) and predicts mortality. In the largest multi-ancestry genome-wide association meta-analysis of lung function to date, comprising 580,869 participants, we identified 1,020 independent association signals implicating 559 genes supported by ≥2 criteria from a systematic variant-to-gene mapping framework. These genes were enriched in 29 pathways. Individual variants showed heterogeneity across ancestries, age and smoking groups, and collectively as a genetic risk score showed strong association with COPD across ancestry groups. We undertook phenome-wide association studies for selected associated variants as well as trait and pathway-specific genetic risk scores to infer possible consequences of intervening in pathways underlying lung function. We highlight new putative causal variants, genes, proteins and pathways, including those targeted by existing drugs. These findings bring us closer to understanding the mechanisms underlying lung function and COPD, and should inform functional genomics experiments and potentially future COPD therapies.
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| 49. |
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| 50. |
- Abolfathi, Bela, et al.
(författare)
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The LSST DESC DC2 Simulated Sky Survey
- 2021
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Ingår i: Astrophysical Journal Supplement Series. - : American Astronomical Society. - 0067-0049 .- 1538-4365. ; 253:31
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Tidskriftsartikel (refereegranskat)abstract
- We describe the simulated sky survey underlying the second data challenge (DC2) carried out in preparation for analysis of the Vera C. Rubin Observatory Legacy Survey of Space and Time (LSST) by the LSST Dark Energy Science Collaboration (LSST DESC). Significant connections across multiple science domains will be a hallmark of LSST; the DC2 program represents a unique modeling effort that stresses this interconnectivity in a way that has not been attempted before. This effort encompasses a full end-to-end approach: starting from a large N-body simulation, through setting up LSST-like observations including realistic cadences, through image simulations, and finally processing with Rubin's LSST Science Pipelines. This last step ensures that we generate data products resembling those to be delivered by the Rubin Observatory as closely as is currently possible. The simulated DC2 sky survey covers six optical bands in a wide-fast-deep area of approximately 300 deg2, as well as a deep drilling field of approximately 1 deg2. We simulate 5 yr of the planned 10 yr survey. The DC2 sky survey has multiple purposes. First, the LSST DESC working groups can use the data set to develop a range of DESC analysis pipelines to prepare for the advent of actual data. Second, it serves as a realistic test bed for the image processing software under development for LSST by the Rubin Observatory. In particular, simulated data provide a controlled way to investigate certain image-level systematic effects. Finally, the DC2 sky survey enables the exploration of new scientific ideas in both static and time domain cosmology.
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