81,994 research outputs found
Photometry Results for the Globular Clusters M10 and M12: Extinction Maps, Color-Magnitude Diagrams, and Variable Star Candidates
We report on photometry results of the equatorial globular clusters (GCs) M10
and M12. These two clusters are part of our sample of GCs which we are probing
for the existence of photometrically varying eclipsing binary stars. During the
search for binaries in M10 and M12, we discovered the signature of differential
reddening across the fields of the clusters. The effect is stronger for M10
than for M12. Using our previously described dereddening technique, we create
differential extinction maps for the clusters which dramatically improve the
appearance of the color-magnitude diagrams (CMDs). Comparison of our maps with
the dust emissivity maps of Schlegel, Finkbeiner, & Davis (SFD) shows good
agreement in terms of spatial extinction features. Several methods of adding an
E_{V-I} zero point to our differential maps are presented of which isochrone
fitting proved to be the most successful. Our E_{V-I} values fall within the
range of widely varying literature values. More specifically, our reddening
zero point estimate for M12 agrees well with the SFD estimate, whereas the one
for M10 falls below the SFD value. Our search for variable stars in the
clusters produced a total of five variables: three in M10 and two in M12. The
M10 variables include a binary system of the W Ursa Majoris (W UMa) type, a
background RR Lyrae star, and an SX Phoenicis pulsator, none of which is
physically associated with M10. M12's variables are two W UMa binaries, one of
which is most likely a member of the cluster. We present the phased photometry
lightcurves for the variable stars, estimate their distances, and show their
locations in the fields and the CMDs of the GCs.Comment: 22 pages, 21 figures, to be published in AJ October 2002. For a
higher-resolution version of this paper, please visit
http://www.astro.lsa.umich.edu/~kaspar/M10_M12_photometry.ps.gz (gzipped
postscript) or http://www.astro.lsa.umich.edu/~kaspar/M10_M12_photometry.pdf
(pdf file
TNT equivalency of M10 propellant
Peak, side-on blast overpressure and scaled, positive impulse have been measured for M10 single-perforated propellant, web size 0.018 inches, using configurations that simulate the handling of bulk material during processing and shipment. Quantities of 11.34, 22.7, 45.4, and 65.8 kg were tested in orthorhombic shipping containers and fiberboard boxes. High explosive equivalency values for each test series were obtained as a function of scaled distance by comparison to known pressure, arrival time and impulse characteristics for hemispherical TNT surface bursts. The equivalencies were found to depend significantly on scaled distance, with higher values of 150-100 percent (pressure) and 350-125 percent (positive impulse) for the extremes within the range from 1.19 to 3.57 m/cube root of kg. Equivalencies as low as 60-140 percent (pressure) and 30-75 percent (positive impulse) were obtained in the range of 7.14 to 15.8 m/cube root of kg. Within experimental error, both peak pressure and positive impulse scaled as a function of charge weight for all quantities tested in the orthorhombic configuration
Constraining Intermediate-Mass Black Holes in Globular Clusters
Decades after the first predictions of intermediate-mass black holes (IMBHs)
in globular clusters (GCs) there is still no unambiguous observational evidence
for their existence. The most promising signatures for IMBHs are found in the
cores of GCs, where the evidence now comes from the stellar velocity
distribution, the surface density profile, and, for very deep observations, the
mass-segregation profile near the cluster center. However, interpretation of
the data, and, in particular, constraints on central IMBH masses, require the
use of detailed cluster dynamical models. Here we present results from Monte
Carlo cluster simulations of GCs that harbor IMBHs. As an example of
application, we compare velocity dispersion, surface brightness and
mass-segregation profiles with observations of the GC M10, and constrain the
mass of a possible central IMBH in this cluster. We find that, although M10
does not seem to possess a cuspy surface density profile, the presence of an
IMBH with a mass up to 0.75% of the total cluster mass, corresponding to about
600 Msun, cannot be excluded. This is also in agreement with the surface
brightness profile, although we find it to be less constraining, as it is
dominated by the light of giants, causing it to fluctuate significantly. We
also find that the mass-segregation profile cannot be used to discriminate
between models with and without IMBH. The reason is that M10 is not yet
dynamically evolved enough for the quenching of mass segregation to take
effect. Finally, detecting a velocity dispersion cusp in clusters with central
densities as low as in M10 is extremely challenging, and has to rely on only
20-40 bright stars. It is only when stars with masses down to 0.3 Msun are
included that the velocity cusp is sampled close enough to the IMBH for a
significant increase above the core velocity dispersion to become detectable.Comment: 30 pages, 8 figures, submitted to Ap
In-season internal and external training load quantification of an elite European soccer team
Elite soccer teams that participate in European competitions need to have players in the best physical and psychological status possible to play matches. As a consequence of congestive schedule, controlling the training load (TL) and thus the level of effort and fatigue of players to reach higher performances during the matches is therefore critical. Therefore, the aim of the current study was to provide the first report of seasonal internal and external training load that included Hooper Index (HI) scores in elite soccer players during an in-season period. Nineteen elite soccer players were sampled, using global position system to collect total distance, high-speed distance (HSD) and average speed (AvS). It was also collected session rating of perceived exertion (s-RPE) and HI scores during the daily training sessions throughout the 2015-2016 in-season period. Data were analysed across ten mesocycles (M: 1 to 10) and collected according to the number of days prior to a one-match week. Total daily distance covered was higher at the start (M1 and M3) compared to the final mesocycle (M10) of the season. M1 (5589m) reached a greater distance than M5 (4473m) (ES = 9.33 [12.70, 5.95]) and M10 (4545m) (ES = 9.84 [13.39, 6.29]). M3 (5691m) reached a greater distance than M5 (ES = 9.07 [12.36, 5.78]), M7 (ES = 6.13 [8.48, 3.79]) and M10 (ES = 9.37 [12.76, 5.98]). High-speed running distance was greater in M1 (227m), than M5 (92m) (ES = 27.95 [37.68, 18.22]) and M10 (138m) (ES = 8.46 [11.55, 5.37]). Interestingly, the s-RPE response was higher in M1 (331au) in comparison to the last mesocycle (M10, 239au). HI showed minor variations across mesocycles and in days prior to the match. Every day prior to a match, all internal and external TL variables expressed significant lower values to other days prior to a match (p<0.01). In general, there were no differences between player positions. Conclusions: Our results reveal that despite the existence of some significant differences between mesocycles, there were minor changes across the in-season period for the internal and external TL variables used. Furthermore, it was observed that MD-1 presented a reduction of external TL (regardless of mesocycle) while internal TL variables did not have the same record during in-season match-day-minus.: The authors state that there were no salaries’ fund from a tobacco company. Also, the authors are not aware of any competing interests. This project was supported by the National Funds through FCT—Portuguese Foundation for Science and Technology (UID/DTP/04045/2013)—and the European Fund for Regional Development (FEDER) allocated by European Union through the COMPETE 2020 Programme (POCI-01-0145- FEDER-006969)—competitiveness and internationalization (POCI). All funding received for this work from any of the following organizations: National Institutes of Health (NIH); Welcome Trust; Howard Hughes Medical Institute (HHMI). The
funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.info:eu-repo/semantics/publishedVersio
Flight measured and calculated exhaust jet conditions for an F100 engine in an F-15 airplane
The exhaust jet conditions, in terms of temperature and Mach number, were determined for a nozzle-aft end acoustic study flown on an F-15 aircraft. Jet properties for the F100 EMD engines were calculated using the engine manufacturer's specification deck. The effects of atmospheric temperature on jet Mach number, M10, were calculated. Values of turbine discharge pressure, PT6M, jet Mach number, and jet temperature were calculated as a function of aircraft Mach number, altitude, and power lever angle for the test day conditions. At a typical test point with a Mach number of 0.9, intermediate power setting, and an altitude of 20,000 ft, M10 was equal to 1.63. Flight measured and calculated values of PT6M were compared for intermediate power at altitudes of 15500, 20500, and 31000 ft. It was found that at 31000 ft, there was excellent agreement between both, but for lower altitudes the specification deck overpredicted the flight data. The calculated jet Mach numbers were believed to be accurate to within 2 percent
Deep multi-telescope photometry of NGC 5466. II. The radial behaviour of the mass function slope
We use a combination of data acquired with the Advanced Camera for Survey
(ACS) on board the Hubble Space Telescope and the Large Binocular Camera
(LBC-blue) mounted on the Large Binocular Telescope, to sample the main
sequence stars of the globular cluster NGC~5466 in the mass range
. We derive the cluster's Luminosity Function in several
radial regions, from the center of the cluster out to the tidal radius. After
corrections for incompleteness and field-contamination, this has been compared
to theoretical Luminosity Functions, obtained by multiplying a simple power law
Mass Function in the form dN/dm by the derivative of the
mass-luminosity relationship of the best-fit isochrone. We find that
varies from -0.6 in the core region to -1.9 in the outer region. This fact
allows us to observationally prove that the stars in NGC 5466 have experienced
the effects of mass segregation. We compare the radial variation of
from the center out to 5 core radii (r) in NGC 5466 and the globular
cluster M10, finding that the gradient of in the first 5r is more
than a factor of 2 shallower in NGC 5466 than in M10, in line with the
differences in the clusters' relaxation timescales. NGC 5466 is dynamically
younger than M10, with two-body relaxation processes only recently starting to
shape the distribution of main sequence stars. This result fully agrees with
the conclusion obtained in our previous works on the radial distribution of
Blue Straggler Stars, further confirming that this can be used as an efficient
clock to measure the dynamical age of stellar systems.Comment: Accepted for publications on Ap
Simulation of the CryoSat-2 satellite radar altimeter sea ice thickness retrieval uncertainty
Crystallization and preliminary diffraction studies of morphinone reductase, a flavoprotein involved in the degradation of morphine alkaloids
Morphinone reductase from Pseudomonas putida M10, a flavoprotein involved in the degradation of morphine alkaloids, was purified from an overexpressing strain of Escherichia coli and crystallized using the hanging-drop vapour-diffusion method. Diffraction data were collected to 2.5 Å. The I-centred orthorhombic cell has a monomer in the asymmetric trait. Preliminary molecular replacement calculations have been performed using Old Yellow Enzyme as the search model
A ground-based proper motion study of twelve nearby Globular Clusters
We derive relative proper motions of stars in the fields of the globular
clusters M12, NGC 6362, M4, M55, M22, NGC 6752, NGC 3201, M30, M10, NGC 362,
M5, and 47 Tucanae based on data collected between 1997 and 2015 with the 1-m
Swope telescope of Las Campanas Observatory. We determine membership class and
membership probability for over 446 000 objects, and show that these are
efficient methods for separating field stars from members of the cluster. In
particular, membership probabilities of variable stars and blue/yellow/red
stragglers are determined. Finally, we find absolute proper motions for six
globular clusters from our sample: M55, NGC 3201, M10, NGC 362, M5, and 47 Tuc.
An electronic catalogue of the derived proper motions is publicly available via
the internet.Comment: 24 pages, 35 figures, 6 tables. Accepted for publication in MNRAS.
Figures of high quality on reques
Prediction of a novel monoclinic carbon allotrope
A novel allotrope of carbon with symmetry was identified during an
\emph{ab-initio} minima-hopping structural search which we call -carbon.
This structure is predicted to be more stable than graphite at pressures above
14.4 GPa and consists purely of bonds. It has a high bulk modulus and is
almost as hard as diamond. A comparison of the simulated X-ray diffraction
pattern shows a good agreement with experimental results from cold compressed
graphite.Comment: 3 pages, 3 figure
- …
