4,871,344 research outputs found
Search for gravitational waves from binary inspirals in S3 and S4 LIGO data
We report on a search for gravitational waves from the coalescence of compact
binaries during the third and fourth LIGO science runs. The search focused on
gravitational waves generated during the inspiral phase of the binary
evolution. In our analysis, we considered three categories of compact binary
systems, ordered by mass: (i) primordial black hole binaries with masses in the
range 0.35 M(sun) < m1, m2 < 1.0 M(sun), (ii) binary neutron stars with masses
in the range 1.0 M(sun) < m1, m2 < 3.0 M(sun), and (iii) binary black holes
with masses in the range 3.0 M(sun)< m1, m2 < m_(max) with the additional
constraint m1+ m2 < m_(max), where m_(max) was set to 40.0 M(sun) and 80.0
M(sun) in the third and fourth science runs, respectively. Although the
detectors could probe to distances as far as tens of Mpc, no gravitational-wave
signals were identified in the 1364 hours of data we analyzed. Assuming a
binary population with a Gaussian distribution around 0.75-0.75 M(sun), 1.4-1.4
M(sun), and 5.0-5.0 M(sun), we derived 90%-confidence upper limit rates of 4.9
yr^(-1) L10^(-1) for primordial black hole binaries, 1.2 yr^(-1) L10^(-1) for
binary neutron stars, and 0.5 yr^(-1) L10^(-1) for stellar mass binary black
holes, where L10 is 10^(10) times the blue light luminosity of the Sun.Comment: 12 pages, 11 figure
Potential of a sunflower seed by-product as animal fat replacer in healthier Frankfurters
Upcycled defatted sunflower seed flour (SUN), a by-product obtained from sunflower oil extraction, was used as an animal fat replacer to develop healthier frankfurters. For that end, animal fat was replaced (~50%) with water and 2% or 4% of SUN. Nutritional composition, technological, structural and sensorial properties were evaluated. SUN incorporation led to a significant increase in protein, minerals (magnesium, potassium, copper and manganese) and a decrease in fat content (~37% less than control with all animal fat). The incorporation of SUN in frankfurters promoted the presence of phenolic compounds. Increasing SUN addition lead to an increasingly (p < 0.05) darker frankfurter colour. Samples with SUN at 4% were firmer than the control according to TPA and sensory analysis results and showed the highest lipid disorder attributed to more lipid interactions in the meat matrix. SUN addition as an animal fat replacer in frankfurters is a feasible strategy to valorise sunflower oil by-products and obtain healthier frankfurters
Sun shield
A shading device which is capable of compactly storing a flexible shade on a biased, window shade type spring roller is disclosed. It is controlled to deliver the shade selectively to either its operative shading or compact storage orientation
Detection of the temporal variation of the sun's cosmic ray shadow with the IceCube detector
We report on the observation of a deficit in the cosmic ray flux from the directions of the Moon and Sun with five years of data taken by the IceCube Neutrino Observatory. Between 2010 May and 2011 May the IceCube detector operated with 79 strings deployed in the glacial ice at the South Pole, and with 86 strings between 2011 May and 2015 May. A binned analysis is used to measure the relative deficit and significance of the cosmic ray shadows. Both the cosmic ray Moon and Sun shadows are detected with high statistical significance (> 10 sigma) for each year. The results for the Moon shadow are consistent with previous analyses and verify the stability of the IceCube detector over time. This work represents the first observation of the Sun shadow with the IceCube detector. We show that the cosmic ray shadow of the Sun varies with time. These results make it possible to study cosmic ray transport near the Sun with future data from IceCube
A sun sensor implemented with an asynchronous luminance vision sensor
A sun sensor implemented with a spiking pixel matrix is reported. It is the very first one based on an asynchronous event-based pixel array. A paradigm associated to classic digital sun sensors is solved with this approach. Only pixels illuminated by the sun light are readout. Hence, the output data flow is quite reduced. The computational load to resolve the sun position is quite low, comparing to prior sensors. Sensor's latency is in the order of milliseconds. The advantages over implementations with APS pixels are more reduced data flow, less latency, and higher dynamic range.Universidad de Cádiz PR2016-072Ministerio de Economía y Competitividad TEC2015-66878- C3-1-RJunta de Andalucía TIC 2012-2338Office of Naval Research (USA) N00014141035
A Prediction Formula of Supersoft X-ray Phase of Classical Novae
On the basis of the recently developed universal decline law of classical
novae, we propose prediction formulae for supersoft X-ray on and off times,
i.e., t_{X-on} = (10 \pm 1.8) t_3 days and t_{X-off} = (5.3 \pm 1.4)
(t_3)^{1.5} days for 8 < t_3 < 80 days. We have determined the absolute
magnitude of our free-free emission model light curves and derived maximum
magnitude vs. rate of decline (MMRD) relations. Our theoretical MMRD relations
are governed by two parameters, one is the white dwarf (WD) mass and the other
is the initial envelope mass at a nova outburst; this second parameter explains
the scatter of MMRD points of individual novae. Our theoretical MMRD relations
are also in good agreement with the well-known empirical formulae. We also show
another empirical relation of M_V(15) ~ -5.7 \pm 0.3 based on the absolute
magnitude of our model light curves, i.e., the absolute magnitude at 15 days
after optical maximum is almost common among various novae. We analyzed ten
nova light curves, in which a supersoft X-ray phase was detected, and estimated
their WD masses. The models best reproducing simultaneously the optical and
supersoft X-ray observations are ONeMg WDs with 1.28 \pm 0.04 M_\sun (V598
Pup), 1.23 \pm 0.05 M_\sun (V382 Vel), 1.15 \pm 0.06 M_\sun (V4743 Sgr), 1.13
\pm 0.06 M_\sun (V1281 Sco), 1.2 \pm 0.05 M_\sun (V597 Pup), 1.06 \pm 0.07
M_\sun (V1494 Aql), 1.04 \pm 0.07 M_\sun (V2467 Cyg), 1.07 \pm 0.07 M_\sun
(V5116 Sgr), 1.05 \pm 0.05 M_\sun (V574 Pup), and a CO WD with 0.93 \pm 0.08
M_\sun (V458 Vul). The newly proposed relationships are consistent with the
emergence or decay epoch of the supersoft X-ray phase of these ten novae.
Finally, we discuss the mechanism of shock-origin hard X-ray component in
relation to the emergence of companion star from the WD envelope.Comment: 36 pages, 29 figures, to appear in the Astrophysical Journa
The Centaurus Group and the Outer Halo of NGC 5128: Are they Dynamically Connected?
NGC 5128, a giant elliptical galaxy only Mpc away, is the dominant
member of a galaxy group of over 80 probable members. The Centaurus group
provides an excellent sample for a kinematic comparison between the halo of NGC
5128 and its surrounding satellite galaxies. A new study, presented here, shows
no kinematic difference in rotation amplitude, rotation axis, and velocity
dispersion between the halo of NGC 5128, determined from over of its
globular clusters, and those of the Centaurus group as a whole. These results
suggest NGC 5128 could be behaving in part as the inner component to the galaxy
group, and could have begun as a large initial seed galaxy, gradually built up
by minor mergers and satellite accretions, consistent with simple cold dark
matter models. The mass and mass-to-light ratios in the B-band, corrected for
projection effects, are determined to be
M_{\sun} and M_{\sun}/L_{\sun} for NGC 5128 out to a
galactocentric radius of 45 kpc, and M_{\sun}
and M_{\sun}/L_{\sun} for the Centaurus group, consistent with
previous studies.Comment: 14 pages, 3 tables, 7 figures, Accepted for publication in A
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