6,109 research outputs found
The Asymmetric Thick Disk: A Star Count and Kinematic Analysis. II The Kinematics
We report a kinematic signature associated with the observed asymmetry in the
distribution of thick disk/inner halo stars interior to the Solar circle
described in Paper I. In that paper we found a statistically significant excess
(20% to 25 %) of stars in quadrant I (l ~ 20 deg to 55 deg) both above and
below the plane (b ~ +/- 25 deg to +/- 45 deg) compared to the complementary
region in quadrant IV. We have measured Doppler velocities for 741 stars,
selected according to the same magnitude and color criteria, in the direction
of the asymmetry and in the corresponding fields in quadrant IV. We have also
determined spectral types and metallicities measured from the same spectra. We
not only find an asymmetric distribution in the V_LSR velocities for the stars
in the two regions, but the angular rate of rotation, w, for the stars in
quadrant I reveals a slower effective rotation rate compared to the
corresponding quadrant IV stars. We use our [Fe/H] measurements to separate the
stars into the three primary population groups, halo, thick disk, and disk, and
conclude that it is primarily the thick disk stars that show the slower
rotation in quadrant I. A solution for the radial, tangential and vertical
components of the V_LSR velocities, reveals a significant lag of ~ 80 to 90
km/s in the direction of Galactic rotation for the thick disk stars in quadrant
I, while in quadrant IV, the same population has only a ~ 20 km/s lag. The
results reported here support a rotational lag among the thick disk stars due
to a gravitational interaction with the bar as the most likely explanation for
the asymmetry in both the star counts and the kinematics. The affected thick
disk stars, however, may be associated with the recently discovered Canis Major
debris stream or a similar merger event (abridged).Comment: Accepted for publication in the Astronomical Journa
An economic evaluation of tick line deregulation in Queensland
Rhipicephalus microplus, the cattle tick, is widely distributed across many tropical and subtropical regions of the world and has been identified as the most economically important species of tick across a number of countries. Quarantine boundaries currently limit the spread of the cattle tick into northern New South Wales, parts of South East Queensland, the central parts of the Northern Territory and northern parts of Western Australia. The Queensland tick line (or quarantine boundary) largely follows the 500mm rainfall isohyet until it reaches southern Queensland. As the cattle tick is unlikely to become endemic to regions receiving median rainfall less than 500mm per annum, the region most likely to be effected by a deregulation of the tick line is located in the south east corner of the State âinsideâ the 500mm isohyet but âoutsideâ of the tick line. There are a number of strategies available to beef producers running susceptible cattle within the region impacted by a deregulation of the tick line. For example, they could: o choose to apply acaricides into the foreseeable future, o choose to breed tick resistance into their livestock and apply acaricides during the conversion period, o replace their susceptible breeding herds with tick resistant stock from within the tick endemic region, or o continue with susceptible livestock and implement sufficient quarantine and pest management strategies to reduce the risk of tick infestation to a negligible level The economic evaluation of these strategies indicates that the total costs of deregulation depend upon the type of response made by industry and the level of that response.Resource /Energy Economics and Policy,
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Assistance to Firefighters Program: Distribution of Fire Grant Funding
The Assistance to Firefighters Grant (AFG) Program, also known as fire grants or the FIRE Act grant program, was established by Title XVII of the FY2001 National Defense Authorization Act (P.L. 106-398). Currently administered by the Federal Emergency Management Agency (FEMA), Department of Homeland Security (DHS), the program provides federal grants directly to local fire departments and unaffiliated Emergency Medical Services (EMS) organizations to help address a variety of equipment, training, and other firefighter-related and EMS needs. A related program is the Staffing for Adequate Fire and Emergency Response Firefighters (SAFER) program, which provides grants for hiring, recruiting, and retaining firefighters.
The fire grant program is now in its 13th year. The Fire Act statute was reauthorized in 2012 (Title XVIII of P.L. 112-239) and provides new guidelines on how fire grant money should be distributed. There is no set geographical formula for the distribution of fire grantsâfire departments throughout the nation apply, and award decisions are made by a peer panel based on the merits of the application and the needs of the community. However, the law does require that fire grants be distributed to a diverse mix of fire departments, with respect to type of department (paid, volunteer, or combination), geographic location, and type of community served (e.g., urban, suburban, or rural).
For FY2012, P.L. 112-74, the Consolidated Appropriations Act, provided 337.5 million for AFG and 670 million for firefighter assistance, including 335 million for SAFER. The Continuing Appropriations Resolution, 2013 (P.L. 112-175), funds firefighter assistance programs through the first six months of FY2013 at an increase of 0.612% of the FY2012 level. Therefore, under the FY2013 continuing resolution, AFG is funded at 339.5 million through March 2013.
The 113th Congress will likely consider FY2013 and FY2014 budget appropriations for AFG and SAFER. As is the case with many federal programs, concerns over the federal budget deficit could impact budget levels for AFG and SAFER. At the same time, firefighter assistance budgets will likely receive heightened scrutiny from the fire community, given the local budgetary cutbacks that many fire departments are facing
A solução de controvérsias na OMC
Divulgação dos SUMĂRIOS das obras recentemente incorporadas ao acervo da Biblioteca Ministro Oscar Saraiva do STJ. Em respeito Ă lei de Direitos Autorais, nĂŁo disponibilizamos a obra na Ăntegra. STJ00076934 339.5 A485
ALMA Observations of the Submillimeter Dense Molecular Gas Tracers in the Luminous Type-1 Active Nucleus of NGC 7469
We present ALMA Cycle 1 observations of the central kpc region of the
luminous type-1 Seyfert galaxy NGC 7469 with unprecedented high resolution
(0.5 0.4 = 165 pc 132 pc) at submillimeter wavelengths.
Utilizing the wide-bandwidth of ALMA, we simultaneously obtained HCN(4-3),
HCO(4-3), CS(7-6), and partially CO(3-2) line maps, as well as the 860
m continuum. The region consists of the central 1 component and
the surrounding starburst ring with a radius of 1.5-2.5. Several
structures connect these components. Except for CO(3-2), these dense gas
tracers are significantly concentrated towards the central 1,
suggesting their suitability to probe the nuclear regions of galaxies. Their
spatial distribution resembles well those of centimeter and mid-infrared
continuum emissions, but it is anti-correlated with the optical one, indicating
the existence of dust obscured star formation. The integrated intensity ratios
of HCN(4-3)/HCO(4-3) and HCN(4-3)/CS(7-6) are higher at the AGN position
than at the starburst ring, which is consistent to our previous findings
(submm-HCN enhancement). However, the HCN(4-3)/HCO(4-3) ratio at the AGN
position of NGC 7469 (1.110.06) is almost half of the corresponding value
of the low-luminosity type-1 Seyfert galaxy NGC 1097 (2.00.2), despite the
more than two orders of magnitude higher X-ray luminosity of NGC 7469. But the
ratio is comparable to that of the close vicinity of the AGN of NGC 1068
( 1.5). Based on these results, we speculate that some other heating
mechanisms than X-ray (e.g., mechanical heating due to AGN jet) can contribute
significantly for shaping the chemical composition in NGC 1097.Comment: Fixed typos in the title. 15 pages, 8 figures, 4 tables: accepted for
publication in ApJ. Comments welcom
The Submillimeter Array Polarimeter
We describe the Submillimeter Array (SMA) Polarimeter, a polarization
converter and feed multiplexer installed on the SMA. The polarimeter uses
narrow-band quarter-wave plates to generate circular polarization sensitivity
from the linearly-polarized SMA feeds. The wave plates are mounted in rotation
stages under computer control so that the polarization handedness of each
antenna is rapidly selectable. Positioning of the wave plates is found to be
highly repeatable, better than 0.2 degrees. Although only a single polarization
is detected at any time, all four cross correlations of left- and
right-circular polarization are efficiently sampled on each baseline through
coordinated switching of the antenna polarizations in Walsh function patterns.
The initial set of anti-reflection coated quartz and sapphire wave plates
allows polarimetry near 345 GHz; these plates have been have been used in
observations between 325 and 350 GHz. The frequency-dependent
cross-polarization of each antenna, largely due to the variation with frequency
of the retardation phase of the single-element wave plates, can be measured
precisely through observations of bright point sources. Such measurements
indicate that the cross-polarization of each antenna is a few percent or
smaller and stable, consistent with the expected frequency dependence and very
small alignment errors. The polarimeter is now available for general use as a
facility instrument of the SMA.Comment: To appear in Proc. SPIE 7020, 'Millimeter and Submillimeter Detectors
and Instrumentation'. Uses spie.cl
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