1,550 research outputs found
The leading jet transverse momentum in inclusive jet production and with a loose jet veto
We study the transverse momentum of the leading jet in the limit where the
jet radius is small, . We introduce the leading-jet function to
calculate this cross section for an inclusive jet sample, and the
subleading-jet function when a loose veto on additional jets is imposed, i.e.
. These jet functions are calculated at
next-to-leading order in QCD and the resummation of jet radius logarithms is
explored. We present phenomenological results for Higgs + 1 jet production, for
both the jet and Higgs transverse momentum distribution. We find that, while
the limit of the cross section provides a good description of the
full NLO result, even for values as large as , simply retaining the
leading logarithm at this order does not. Indeed, the NLO contribution to the
hard function and, to a lesser extent, non-logarithmic corrections to the jet
function are sizable and must be included to obtain the correct cross section.
In the inclusive cross section we find that the corrections
are several precent, while in exclusive cross sections at large and
small they can reach 20%. However, it is not clear how important the
resummation of these logarithms is, given the presence of other large
corrections at NNLO.Comment: v3: minor typo corrected, 22 pages, 6 figure
NLO corrections to h → bb¯ decay in SMEFT
We calculate the full set of next-to-leading order (NLO) corrections to h → b b¯¯ decay in the dimension-6 Standard Model Effective Field Theory (SMEFT). Our calculation forms the basis for precision studies of this decay mode in effective field theory, providing analytic and numerical results for contributions of the 45 dimension-6 operators appearing at NLO. On the technical side, we discuss several complications in NLO SMEFT computations which have not yet been addressed in the literature. These include subtleties in Higgs-Z mixing, electric charge renormalization, and especially the treatment of tadpoles in SMEFT. In particular, we highlight the role of decoupling relations in eliminating potentially large tadpole corrections to the decay rate in hybrid renormalization schemes which employ the MS¯¯¯¯¯¯¯ scheme for some Standard Model parameters (such as the b-quark mass and electric charge) and the on-shell scheme for others
NNLO event generation for production in the SM effective field theory
We consider associated production with and decays in hadronic collisions. In the framework of the Standard Model
effective field theory (SMEFT) we calculate the QCD corrections to this process
and achieve next-to-next-to-leading order plus parton shower (NNLOPS)
accuracy using the MiNNLO method. This precision is obtained for a
subset of six SMEFT operators, including the corrections from effective Yukawa-
and chromomagnetic dipole-type interactions. Missing higher-order QCD effects
associated with the considered dimension-six operators are estimated to have a
relative numerical impact of less than a percent on the total rate once
existing experimental limits on the relevant Wilson coefficients are taken into
account. We provide a dedicated Monte Carlo (MC) code that evaluates the NNLO
SMEFT corrections on-the-fly in the event generation. This MC generator is used
to study the numerical impact of NNLOPS corrections on the kinematic
distributions in production employing
simple SMEFT benchmark scenarios. We identify the invariant mass
of the two -tagged jets as well as the three-invariant jet mass as particularly interesting observables to study SMEFT effects. These
distributions receive contributions that change both their normalisation and
shape with the latter modifications depending on the exact jet definition. To
our knowledge SMEFT effects of this type have so far not been discussed in the
literature. The presented MC generator can also serve as a starting point to
obtain NNLOPS accuracy for a suitable enlarged set of effective operators in
the future.Comment: 32 pages, 7 figure
Resummed differential cross sections for top-quark pairs at the LHC
We present state of the art resummation predictions for differential cross sections in top-quark pair production at the LHC. They are derived from a formalism which allows the simultaneous resummation of both soft and small-mass logarithms, which endanger the convergence of fixed-order perturbative series in the boosted regime, where the partonic center-of-mass energy is much larger than the mass to the top quark. We combine such a double resummation at next-to-next-to-leading logarithmic′ (NNLL′) accuracy with standard soft-gluon resummation at next-to-next-to-leading logarithmic accuracy and with next-to-leading-order calculations, so that our results are applicable throughout the whole phase space. We find that the resummation effects on the differential distributions are significant, bringing theoretical predictions into better agreement with experimental data compared to fixed-order calculations. Moreover, such effects are not well described by the next-to-next-to-leading-order approximation of the resummation formula, especially in the high-energy tails of the distributions, highlighting the importance of all-orders resummation in dedicated studies of boosted top production
Differential Impacts of Online Delivery Methods on Student Learning: A Case Study in Biorenewables
In 2007, a Virtual Education Center for Biorenewable Resources was initiated that offered three distance education courses, one being Biorenewable Resources and Technology (BRT) 501 – Fundamentals of Biorenewable Resources and Technology, the subject of this study. The primary objective was to determine if course delivery method (video lecture format and the other in menu-driven auto-tutorial presentations (MDAP) deliv¬ered via Flash format), student major (agricultural and non-agricultural), and gender influence online student learning in BRT 501. We found that BRT 501 student performance was not significantly impacted by module delivery method. Students with agricultural majors were outperformed by students with non-agricultural majors, most of whom were engineering students, on the midterm and final exams, and course grade. Gender dif¬ferences seen on the biomass-module first-attempt total quiz score disappeared for the final total quiz score on that module
Efavirenz Is Predicted To Accumulate in Brain Tissue: an In Silico, In Vitro, and In Vivo Investigation
Adequate concentrations of efavirenz in the central nervous system (CNS) are necessary to suppress viral replication, but high concentrations may increase the likelihood of CNS adverse drug reactions. The aim of this investigation was to evaluate the efavirenz distribution in the cerebrospinal fluid (CSF) and the brain by using a physiologically based pharmacokinetic (PBPK) simulation for comparison with rodent and human data. The efavirenz CNS distribution was calculated using a permeability-limited model on a virtual cohort of 100 patients receiving efavirenz (600 mg once daily). Simulation data were then compared with human data from the literature and with rodent data. Wistar rats were administered efavirenz (10 mg kg of body weight(−1)) once daily over 5 weeks. Plasma and brain tissue were collected for analysis via liquid chromatography-tandem mass spectrometry (LC-MS/MS). The median maximum concentrations of drug (C(max)) were predicted to be 3,184 ng ml(−1) (interquartile range [IQR], 2,219 to 4,851 ng ml(−1)), 49.9 ng ml(−1) (IQR, 36.6 to 69.7 ng ml(−1)), and 50,343 ng ml(−1) (IQR, 38,351 to 65,799 ng ml(−1)) in plasma, CSF, and brain tissue, respectively, giving a tissue-to-plasma ratio of 15.8. Following 5 weeks of oral dosing of efavirenz (10 mg kg(−1)), the median plasma and brain tissue concentrations in rats were 69.7 ng ml(−1) (IQR, 44.9 to 130.6 ng ml(−1)) and 702.9 ng ml(−1) (IQR, 475.5 to 1,018.0 ng ml(−1)), respectively, and the median tissue-to-plasma ratio was 9.5 (IQR, 7.0 to 10.9). Although it is useful, measurement of CSF concentrations may give an underestimation of the penetration of antiretrovirals into the brain. The limitations associated with obtaining tissue biopsy specimens and paired plasma and CSF samples from patients make PBPK modeling an attractive tool for probing drug distribution
Trans World Radio - Culvert Design
Trans World Radio (TWR) is a mission organization focused on broadcasting the Gospel around the world. TWR now serves 190 countries by transmitting in 275 languages, using radio to deliver the message to as many people as possible. The organization’s West Africa Transmitter Site in Benin currently has accessibility problems due to high streamflows and saturated ground conditions during the rainy season. The site also needs a secure perimeter to reduce trespassing and theft.
To address these issues, our client, Garth Kennedy, Director of the West Africa Transmitter Station, has asked the team to design two culverts, one at the upstream property boundary and one at the downstream boundary. Culverts are advantageous for this scenario because they can act as a bridge, while the pipe size can be restricted to inhibit trespassing. Once the culverts are built, the fence and perimeter road can be extended over them.
For both sides of the property, the team has designed a series of U-shaped, pre-cast concrete box culverts. The team calculated the design flows based on rainfall data and the topography of the site to determine the size and number of box sections. The team has also designed the culverts and the supporting concrete structures to bear the load of vehicles and the machinery on site. TWR plans to construct the pre-cast culverts on-site, and then build the supporting structures and install the culverts during their dry season.https://mosaic.messiah.edu/engr2021/1017/thumbnail.jp
- …