3,004 research outputs found
Readout and Control of a Power-recycled Interferometric Gravitational-wave Antenna
Interferometric gravitational wave antennas are based on Michelson
interferometers whose sensitivity to small differential length changes has been
enhanced by adding multiple coupled optical resonators. The use of optical
cavities is essential for reaching the required sensitivity, but sets
challenges for the control system which must maintain the cavities near
resonance. The goal for the strain sensitivity of the Laser Interferometer
Gravitational-wave Observatory (LIGO) is 10^-21 rms, integrated over a 100 Hz
bandwidth centered at 150 Hz. We present the major design features of the LIGO
length and frequency sensing and control system which will hold the
differential length to within 5 10^-14 m of the operating point. We also
highlight the restrictions imposed by couplings of noise into the gravitational
wave readout signal and the required immunity against them.Comment: Presentation at ICALEPCS 2001, San Jose, November 2001, (WECT003), 3
page
Diagnosis and treatment of hereditary angioedema with normal C1 inhibitor
Until recently it was assumed that hereditary angioedema is a disease that results exclusively from a genetic deficiency of the C1 inhibitor. In 2000, families with hereditary angioedema, normal C1 inhibitor activity and protein in plasma were described. Since then numerous patients and families with that condition have been reported. Most of the patients by far were women. In many of the affected women, oral contraceptives, hormone replacement therapy containing estrogens, and pregnancies triggered the clinical symptoms. Recently, in some families mutations in the coagulation factor XII (Hageman factor) gene were detected in the affected persons
Infrared Finite Observables in N=8 Supergravity
Using the algorithm of constructing the IR finite observables suggested and discussed in details in our previous publications, we consider construction of such observables in N=8 SUGRA in NLO of PT. In general, contrary to the amplitudes defined in the presence of some IR regulator, such observables do not reveal any simple structure
Bank Competition and Firm Growth in the Enlarged European Union
We examine the impact of bank competition and institutional factors on net firm entry in a sample of European manufacturing industries over the 1995-2006 period. Taking into account industry differences in the need for external finance, we find that bank competition helps firm entry. In addition, better institutions - especially legal structure and property rights - also have a positive impact, particularly through a better functioning financial system
Assessing the winter hardiness of perennial cereal rye relative to winter cereals traditionally grown in western Canada
Non-Peer ReviewedPerennial cereal (PC) rye (Secale cereale x S. montanum) is reported to be a three to four year perennial forage crop. At AAFC-Swift Current, SK, PC rye was compared to three winter triticale varieties (Pika, Prego, and Bobcat), CDC Clair winter wheat and Prima fall rye for winter hardiness. Small plots were seeded at six dates (July 18, Aug. 3, Aug. 16, Aug. 30, Sept. 7, and Sept. 17) in 2001, with a defoliation treatment occurring during the first week of October. When compared to the winter cereals for winter survival under field conditions, PC rye was tied for second for a mid-July seeding date, and tied for first for early and mid-Aug. seeding dates. PC rye survival was not different (P>0.05) between varieties for late Aug. and Sept. seeding
dates. Results found the optimum time to plant PC rye to ensure maximum winter hardiness was mid-to-late Aug. PC rye was sensitive to late-fall defoliation with the greatest survival reduction occurring for the mid-July seeding date
Construction of Infrared Finite Observables in N=4 Super Yang-Mills Theory
In this paper we give all the details of the calculation that we presented in
our previous paper ArXiv:0908.0387 where the infrared structure of the MHV
gluon amplitudes in the planar limit for super Yang-Mills theory
was considered in the next-to-leading order of perturbation theory. Explicit
cancellation of the infrared divergencies in properly defined inclusive
cross-sections is demonstrated first in a toy model example of "conformal QED"
and then in the real SYM theory. We give the full-length details
both for the calculation of the real emission and for the diagrams with
splitting in initial and final states. The finite parts for some inclusive
differential cross-sections are presented in an analytical form. In general,
contrary to the virtual corrections, they do not reveal any simple structure.
An example of the finite part containing just the log functions is presented.
The dependence of inclusive cross-section on the external scale related to the
definition of asymptotic states is discussed.Comment: 49 pages, LATEX, 6 eps figures; Minor changes, Refs adde
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