1,693 research outputs found
Reaching silicon-based NEMS performances with 3D printed nanomechanical resonators
No full textThe extreme miniaturization in NEMS resonators offers the possibility to reach an unprecedented resolution in high-performance mass sensing. These very low limits of detection are related to the combination of two factors: a small resonator mass and a high quality factor. The main drawback of NEMS is represented by the highly complex, multi-steps, and expensive fabrication processes. Several alternatives fabrication processes have been exploited, but they are still limited to MEMS range and very low-quality factor. Here we report the fabrication of rigid NEMS resonators with high-quality factors by a 3D printing approach. After a thermal step, we reach complex geometry printed devices composed of ceramic structures with high Young’s modulus and low damping showing performances in line with silicon-based NEMS resonators ones. We demonstrate the possibility of rapid fabrication of NEMS devices that present an effective alternative to semiconducting resonators as highly sensitive mass and force sensors
Recommended from our members
Supernovae and high density nuclear matter
No full textThe role of the nuclear equation of state (EOS) in producing prompt supernova explosions is examined. Results of calculations of Baron, Cooperstein, and Kahana incorporating general relativity and a new high density EOS are presented, and the relevance of these calculations to laboratory experiments with heavy ions considered. 31 refs., 6 figs., 2 tabs
Search for a Standard Model Higgs boson produced in association with a W or Z boson decaying to bottom quarks
No full textA search for a Standard Model Higgs boson decaying to b produced in association with a W or Z boson is reported for the following channels W(e)H, W()H, W()H, Z(H, Z(ee)H, and Z()H. The search is performed on data samples corresponding to integrated luminosities of 5.1 at TeV and 18.9 at TeV, collected by the CMS experiement at the LHC. An excess of events is observed above the expected background with a local significance of 2.1 standard deviations for a Higgs boson with mass 125 GeV consistent with Standard Model expectations. The signal strength corresponding to this excess, relative to that of the Standard Model Higgs boson, was 0.89 0.43
Symplectic subspaces of symplectic Grassmannians
No full textAbstractLet V be a non-degenerate symplectic space of dimension 2n over the field F and for a natural number l<n denote by Cl(V) the incidence geometry whose points are the totally isotropic l-dimensional subspaces of V. Two points U,W of Cl(V) will be collinear when W⊂U⊥ and dim(U∩W)=l−1 and then the line on U and W will consist of all the l-dimensional subspaces of U+W which contain U∩W. The isomorphism type of this geometry is denoted by Cn,l(F). When char(F)≠2 we classify subspaces S of Cl(F) where S≅Cm,k(F)
Recommended from our members
Critical study of type II supernovae: equations of state and general relativity
No full textThe relevance of relativistic gravitation and of the properties of nuclear matter at high density to supernova explosions is examined in detail. The existing empirical knowledge on the nuclear equation of state at densities greater than saturation, extracted from analysis of heavy ion collisions and from the breathing mode in heavy nuclei, is also considered. Particulars of the prompt explosions recently obtained theoretically by Baron, Cooperstein, and Kahana are presented. 40 refs., 9 figs., 3 tabs
Observation of Higgs boson decay to bottom quarks
No full textThe observation of the Standard Model Higgs boson decay to a bottom quark-antiquark pair is presented. The primary contribution to this result is from processes in which the Higgs boson is produced in association with a W or Z boson. The latest measurement of these processes is described, using 41.3/fb of proton-proton collision data at center-of-mass energy √s = 13 TeV, collected by the CMS experiment in 2017. The significance of the observed excess in data over Standard Model backgrounds is 3.3 standard deviations. The result is combined with similar measurements performed by CMS on previous datasets, resulting in an observed significance of 5.6 standard deviations. The measured signal is well consistent with the Standard Model expectation for a Higgs boson with mass 125 GeV decaying to bottom quarks, with a precision of 20%
Observation of Higgs boson decay to bottom quarks
No full textThe observation of the Standard Model Higgs boson decay to a bottom quark-antiquark pair is presented. The primary contribution to this result is from processes in which the Higgs boson is produced in association with a W or Z boson. The latest measurement of these processes is described, using 41.3/fb of proton-proton collision data at center-of-mass energy √s = 13 TeV, collected by the CMS experiment in 2017. The significance of the observed excess in data over Standard Model backgrounds is 3.3 standard deviations. The result is combined with similar measurements performed by CMS on previous datasets, resulting in an observed significance of 5.6 standard deviations. The measured signal is well consistent with the Standard Model expectation for a Higgs boson with mass 125 GeV decaying to bottom quarks, with a precision of 20%
Observation of Higgs boson decay to bottom quarks
No full textThe observation of the Standard Model Higgs boson decay to a bottom quark-antiquark pair is presented. The primary contribution to this result is from processes in which the Higgs boson is produced in association with a W or Z boson. The latest measurement of these processes is described, using 41.3 fb of proton-proton collision data at center-of-mass energy = 13 TeV, collected by the CMS experiment in 2017. The significance of the observed excess in data over Standard Model backgrounds is 3.3 standard deviations. The result is combined with similar measurements performed by CMS on previous datasets, resulting in an observed significance of 5.6 standard deviations. The measured signal is well consistent with the Standard Model expectation for a Higgs boson with m = 125 GeV decaying to bottom quarks, with a precision of 20%
Can Nuclear Power Be Part of the Solution?
No full textThe author discusses the importance of incorporating the full costs of operating a nuclear power plant in the U.S., such as climate impact, risk of accidents, and safe disposal of radioactive waste. He argues on the need for changes in the country\u27s evaluation of nuclear power which include the elimination of subsidies, and the requirement to buy full-coverage insurance for accidents. The author further highlights the cost of greenhouse gas emissions from nuclear power plants
- …
