1,423,411 research outputs found
Hyperbolicity in Teichm\"uller space
We review and organize some results describing the behavior of a
Teichm\"uller geodesic and draw several applications: 1) We show that
Teichm\"uller geodesics do not back track. 2) We show that a Teichm\"uller
geodesic segment whose endpoints are in the thick part has the fellow
travelling property. This fails when the endpoints are not necessarily in the
thick part. 3) We show that if an edge of a Teichm\"uller geodesic triangle
passes through the thick part, then it is close to one of the other egdes.Comment: 26 pages, 2 figure
Three-dimensional adaptive evolution of gravitational waves in numerical relativity
Adaptive techniques are crucial for successful numerical modeling of
gravitational waves from astrophysical sources such as coalescing compact
binaries, since the radiation typically has wavelengths much larger than the
scale of the sources. We have carried out an important step toward this goal,
the evolution of weak gravitational waves using adaptive mesh refinement in the
Einstein equations. The 2-level adaptive simulation is compared with unigrid
runs at coarse and fine resolution, and is shown to track closely the features
of the fine grid run.Comment: REVTeX, 7 pages, including three figures; submitted to Physical
Review
Medium-Energy Gamma-Ray Astrophysics with the 3-DTI Gamma-Ray Telescope
Gamma-ray observations in the medium energy range (0.50-50.0 MeV) are central to unfolding many outstanding questions in astrophysics. The challenges of medium-energy gamma-ray observations, however, are the low photon statistics and large backgrounds. We review these questions, address the telescope technology requirements, and describe our development of the 3-Dimensional Track Imaging (3-DTI) Compton telescope and its performance for a new mediumenergy gamma-ray mission. The 3-DTI is a large-volume time projection chamber (TPC) with a 2-dimensional gas micro-well detector (MWD) readout
PELATIHAN FITUR TRACK CHANGES PADA MICROSOFT WORD UNTUK MAHASISWA JURUSAN PETERNAKAN DI POLBANGTAN YOGYAKARTA-MAGELANG
Microsoft word is a word processing software in document creation that is the mainstay of Microsoft. In this software there is a track changes feature which functions to track changes made by the reviewer in carrying out the review work. The purpose of the training is to train students in using the track changes feature in Microsoft Word. The training conducted at the Polbangtan Yogyakarta-Magelang hall is a form of community service, especially students. The stages of service are 1. socialization of the track changes feature in Microsoft word; 2. carry out training on these features by students; 3. evaluation of training programs. The result of community service is that post-training Polbangtan livestock department students are able to apply the track changes feature in Microsoft word software
Development of a telescope for medium-energy gamma-ray astronomy
The Advanced Energetic Pair Telescope (AdEPT) is being developed at GSFC as a future NASA MIDEX mission to explore the medium-energy (5–200 MeV) gamma-ray range. The enabling technology for AdEPT is the Three- Dimensional Track Imager (3-DTI), a gaseous time projection chamber. The high spatial resolution 3-D electron tracking of 3-DTI enables AdEPT to achieve high angular resolution gamma-ray imaging via pair production and triplet production (pair production on electrons) in the medium-energy range. The low density and high spatial resolution of 3-DTI allows the electron positron track directions to be measured before they are dominated by Coulomb scattering. Further, the significant reduction of Coulomb scattering allows AdEPT to be the first medium-energy gamma-ray telescope to have high gamma-ray polarization sensitivity. We review the science goals that can be addressed with a medium-energy pair telescope, how these goals drive the telescope design, and the realization of this design with AdEPT. The AdEPT telescope for a future MIDEX mission is envisioned as a 8 m3 active volume filled with argon at 2 atm. The design and performance of the 3-DTI detectors for the AdEPT telescope are described as well as the outstanding instrument challenges that need to be met for the AdEPT mission
Charged Fermions Below 100 GeV
How light can a fermion be if it has unit electric charge? We revisit the
lore that LEP robustly excludes charged fermions lighter than about 100 GeV. We
review LEP chargino searches, and find them to exclude charged fermions lighter
than 90 GeV, assuming a higgsino-like cross section. However, if the charged
fermion couples to a new scalar, destructive interference among production
channels can lower the LEP cross section by a factor of 3. In this case, we
find that charged fermions as light as 75 GeV can evade LEP bounds, while
remaining consistent with constraints from the LHC. As the LHC collects more
data, charged fermions in the 75-100 GeV mass range serve as a target for
future monojet and disappearing track searches.Comment: 35 pages, 11 figures, 2 table
UNO-OASA- Reappointment, Promotion and Tenure
The information provided here is excerpted from larger university documents. The review of faculty performance involves two separate but related processes:
1. Annual Review:Evaluates faculty members\u27 activities for the current year and determines merit increases for the next year
2. Reappointment, Promotion, and Tenure Review (hereafter referred to as RPT): Evaluates faculty members for continuous appointment, guides tenure decisions Full-time faculty members ore evaluated for annual review only. Tenure-track faculty members ore evaluated for both annual review and reappointment review
Engineering evaluations and studies. Report for Ku-band studies, exhibit A
System performance aspects of the Ku band radar communication hardware and investigations into the Ku band/payload interfaces are discussed. The communications track problem caused by the excessive signal dynamic range at the servo input was investigated. The management/handover logic is discussed and a simplified description of the transmitter enable logic function is presented. Output noise produced by a voltage-controlled oscillator chip used in the SPA return-link channel 3 mid-bit detector is discussed. The deployed assembly (DA) and EA-2 critical design review data are evaluated. Cross coupling effects on antenna servo stability were examined. A series of meetings on the acceptance test specification for the deployed assembly is summarized
Multidimensional optical fractionation with holographic verification
The trajectories of colloidal particles driven through a periodic potential
energy landscape can become kinetically locked in to directions dictated by the
landscape's symmetries. When the landscape is realized with forces exerted by a
structured light field, the path a given particle follows has been predicted to
depend exquisitely sensitively on such properties as the particle's size and
refractive index These predictions, however, have not been tested
experimentally. Here, we describe measurements of colloidal silica spheres'
transport through arrays of holographic optical traps that use holographic
video microscopy to track individual spheres' motions in three dimensions and
simultaneously to measure each sphere's radius and refractive index with
part-per-thousand resolution. These measurements confirm previously untested
predictions for the threshold of kinetically locked-in transport, and
demonstrate the ability of optical fractionation to sort colloidal spheres with
part-per-thousand resolution on multiple characteristics simultaneously.Comment: 4 pages, 2 figures. Accepted for publication in Physical Review
Letter
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