17,735 research outputs found
Living on campus during the 2020-2021 academic year
This entry describes the author\u27s experience living on campus as Eastern Washington University was holding the vast majority of its classes online and the on-campus student population was very small.https://dc.ewu.edu/covid/1032/thumbnail.jp
Chandra Discovery of 10 New X-Ray Jets Associated With FR II Radio Core-Selected AGNs in the MOJAVE Sample
The Chandra X-ray observatory has proven to be a vital tool for studying
high-energy emission processes in jets associated with Active Galactic Nuclei
(AGN).We have compiled a sample of 27 AGN selected from the radio flux-limited
MOJAVE (Monitoring of Jets in AGN with VLBA Experiments) sample of highly
relativistically beamed jets to look for correlations between X-ray and radio
emission on kiloparsec scales. The sample consists of all MOJAVE quasars which
have over 100 mJy of extended radio emission at 1.4 GHz and a radio structure
of at least 3" in size. Previous Chandra observations have revealed X-ray jets
in 11 of 14 members of the sample, and we have carried out new observations of
the remaining 13 sources. Of the latter, 10 have Xray jets, bringing the
overall detection rate to ~ 78%. Our selection criteria, which is based on
highly compact, relativistically beamed jet emission and large extended radio
flux, thus provides an effective method of discovering new X-ray jets
associated with AGN. The detected X-ray jet morphologies are generally well
correlated with the radio emission, except for those displaying sharp bends in
the radio band. The X-ray emission mechanism for these powerful FR II
(Fanaroff-Riley type II) jets can be interpreted as inverse Compton scattering
off of cosmic microwave background (IC/CMB) photons by the electrons in the
relativistic jets. We derive viewing angles for the jets, assuming a
non-bending, non-decelerating model, by using superluminal parsec scale speeds
along with parameters derived from the inverse Compton X-ray model. We use
these angles to calculate best fit Doppler and bulk Lorentz factors for the
jets, as well as their possible ranges, which leads to extreme values for the
bulk Lorentz factor in some cases. When both the non-bending and
non-decelerating assumptions are relaxed [abridged]Comment: 38 Pages, 4 Figures, 5 Tables, accepted for publication in Ap
S22RS SGR No. 26 (Divestment)
A Resolution
To Urge and Request that Louisiana State University divests its stocks, funds, and endowments from companies and institutions that profit from or engage in human rights violations in US prisons, at the US-Mexico Border, in Occupied Palestine, and environmentall
A new invariant on hyperbolic Dehn surgery space
In this paper we define a new invariant of the incomplete hyperbolic
structures on a 1-cusped finite volume hyperbolic 3-manifold M, called the
ortholength invariant. We show that away from a (possibly empty) subvariety of
excluded values this invariant both locally parameterises equivalence classes
of hyperbolic structures and is a complete invariant of the Dehn fillings of M
which admit a hyperbolic structure. We also give an explicit formula for the
ortholength invariant in terms of the traces of the holonomies of certain loops
in M. Conjecturally this new invariant is intimately related to the boundary of
the hyperbolic Dehn surgery space of M.Comment: Published by Algebraic and Geometric Topology at
http://www.maths.warwick.ac.uk/agt/AGTVol2/agt-2-23.abs.htm
Cosmic Ray Accelerators in the Large Magellanic Cloud
I point out a correlation between gamma-ray emissivity and the historical
star formation rate in the Large Magellanic Cloud ~12.5 Myr ago. This
correlation bolsters the view that CRs in the LMC are accelerated by
conglomerations of supernova remnants: i.e. superbubbles and supergiant shells.Comment: Research Not
Differentiation of Capsicum Species via Protein Extraction and SDS-PAGE Analysis: A Two-Day Experiment for Undergraduate Biochemistry Laboratories
The Capsicum genus is comprised of more than 200 varieties of pepper plant that collectively represent only five cultivated spices. As a result of extensive cross-breeding, an 88% similarity in protein coding DNA has developed. While this has made species determination based solely on physical appearance all but impossible, the 12% difference in protein coding DNA has led to subtle differences in translated protein. SDS-PAGE analysis facilitates the generation of protein banding patterns that, after careful analysis, was used to differentiate one variety of pepper from another. This project was used to distinguish between pepper plant species and was carried out as a senior mini-research project in which students had four weeks to develop the project. THe students independently modified an existing protocol to employ safer chemicals and more easily obtainable materials needed in the experiment. After the students developed the protocols, they were then required to lead other students in the laboratory procedures. The educational aspect of this project was successfully completed in two laboratory periods which allowed the students to use a variety of biochemical techniques (such as centrifugation, vacuum filtration, and SDS-PAGE) as well as more specialized procedures including natural product extraction, tissue preparation, and the handling of liquid nitrogen
Kinetic Freeze-out and Radial Flow in 11.6 A GeV Au+Au Collisions
We study the kinetic freeze-out conditions of hadrons in Au+Au collisions at
11.6 A GeV/c using different parametrizations of an expanding thermal fireball.
We take into account the available double differential momentum spectra of a
variety of particle species, covering a large fraction of the total momentum
space. The overall fit to the data is very good and indicates a relatively low
kinetic freeze-out temperature of about 90 MeV with an average transverse
expansion velocity at midrapidity of about 0.5 c.Comment: 5 pages ReVTeX, incl. 3 figures and 2 tables. Revised version with
improved discussion of model and added references. Accepted by Phys. Lett.
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