12 research outputs found
Black Holes in 4 Nearby Radio Galaxies
We study the velocity dispersion profiles of the nuclei of NGC 1326, 2685,
5273 and 5838 in the CO first overtone band. There is evidence for a black hole
(BH) in NGC 1326 and 5838. Gas is seen flowing out of the nuclear region of NGC
5273. We put upper limits on the nuclear BHs responsible for its activity and
that of NGC 2685.Comment: to appear in ApS
Evidence of a link between the evolution of clusters and their AGN fraction
We discuss the optical properties, X-ray detections and active galactic nucleus (AGN) populations of four clusters at z ~ 1 in the Subaru–XMM Deep Field (SXDF). The velocity distribution and plausible extended X-ray detections are examined, as well as the number of X-ray point sources and radio sources associated with the clusters. We find that the two clusters that appear virialized and have an extended X-ray detection contain few, if any, AGN, whereas the two pre-virialized clusters have a large AGN population. This constitutes evidence that the AGN fraction in clusters is linked to the clusters' evolutionary stage. The number of X-ray AGN in the pre-virialized clusters is consistent with an overdensity of a factor of ~200; the radio AGN appear to be clustered with a factor of 3 to 6 higher. The median K-band luminosities of L_K= 1.7 ± 0.7 L* for the X-ray sources and L_K= 2.3 ± 0.1 L* for the radio sources support the theory that these AGN are triggered by galaxy interaction and merging events in sub-groups with low internal velocity distributions, which make up the cluster environment in a pre-virialization evolutionary stage
Infrared Spectroscopy of Nearby Radio Active Elliptical Galaxies
In preparation for a study of their circumnuclear gas we have surveyed 60% of a complete sample of elliptical galaxies within 75 Mpc that are radio sources. Some 20% of our nuclear spectra have infrared emission lines, mostly Paschen lines, Brackett γ, and [Fe II]. We consider the influence of radio power and black hole mass in relation to the spectra. Access to the spectra is provided here as a community resource
The Cosmic Microwave Background & Inflation, Then & Now
The most recent results from the Boomerang, Maxima, DASI, CBI and VSA CMB experiments significantly increase the case for accelerated expansion in the early universe (the inflationary paradigm) and at the current epoch (dark energy dominance). This is especially so when combined with data on high redshift supernovae (SN1) and large scale structure (LSS), encoding information from local cluster abundances, galaxy clustering, and gravitational lensing. There are “7 pillars of Inflation” that can be shown with the CMB probe, and at least 5, and possibly 6, of these have already been demonstrated in the CMB data: (1) the effects of a large scale gravitational potential, demonstrated with COBE/DMR in 1992–96; (2) acoustic peaks/dips in the angular power spectrum of the radiation, which tell about the geometry of the Universe, with the large first peak convincingly shown with Boomerang and Maxima data in 2000, a multiple peak/dip pattern shown in data from Boomerang and DASI (2nd, 3rd peaks, first and 2nd dips in 2001) and from CBI (2nd, 3rd, 4th, 5th peaks, 3rd, 4th dips at 1-sigma in 2002); (3) damping due to shear viscosity and the width of the region over which hydrogen recombination occurred when the universe was 400000 years old (CBI 2002); (4) the primary anisotropies should have a Gaussian distribution (be maximally random) in almost all inflationary models, the best data on this coming from Boomerang; (5) secondary anisotropies associated with nonlinear phenomena subsequent to 400000 years, which must be there and may have been detected by CBI and another experiment, BIMA. Showing the 5 “pillars” involves detailed confrontation of the experimental data with theory; e.g., (5) compares the CBI data with predictions from two of the largest cosmological hydrodynamics simulations ever done. DASI, Boomerang and CBI in 2002, AMiBA in 2003, and many other experiments have the sensitivity to demonstrate the next pillar, (6) polarization, which must be there at the ~ 7% level. A broad-band DASI detection consistent with inflation models was just reported. A 7th pillar, anisotropies induced by gravity wave quantum noise, could be too small to detect. A minimal inflation parameter set, {ω_b, ω_(cdm), Ω_(tot), Ω_Q, W_Q, n_s, τ_C, σ_8}, is used to illustrate the power of the current data. After marginalizing over the other cosmic and experimental variables, we find the current CMB+LSS+SN1 data give Ω_(tot) = 1.00_(-.03_^(+.07), consistent with (non-baroque) inflation theory. Restricting to Ω_(tot) = 1, we find a nearly scale invariant spectrum, n_s = 0.97_(-.05)^(+.06). The CDM density, ω_(cdm) = Ω_(cdm)h^2 = .12_(-.01)^(+.01), and baryon density, ω_b ≡ Ω_bh^2 = .022_(-.002)^(+.003), are in the expected range. (The Big Bang nucleosynthesis estimate is 0.019 ± 0.002.) Substantial dark (unclustered) energy is inferred, Ω_Q ≈ 0.68 ± 0.05, and CMB+LSS Ω_Q values are compatible with the independent SN1 estimates. The dark energy equation of state, crudely parameterized by a quintessence-field pressure-to-density ratio W_Q, is not well determined by CMB+LSS (W_Q < −0.4 at 95% CL), but when combined with SN1 the resulting W_Q < −0.7 limit is quite consistent with the W_Q=−1 cosmological constant case
Coherent Detector Arrays for Millimeter and Submillimeter Astronomy
Progress in many areas of astronomy requires large-area surveys and observations of
extended objects. This includes the cosmic microwave background, nearby galaxies, the
Milky Way, and regions of star-forming regions within our galaxy. The ability to carry
out such studies is critically dependent on the development of affordable high-sensitivity
focal plane arrays, for both spectral line and continuum observations. We discuss a
program for the next decade to develop such technology for ground-based and spacebased
millimeter and submillimeter astronomy. Appropriate technologies exist, but
significant effort is required to make the transition from simply replicating individual
pixels to approaching focal plane array design in an integrated fashion from feeds to
spectrometers for spectral analysis. This advance is essential to realize the full potential
of major new ground-based, suborbital, and future space facilities, and is relevant to the
RMS and EOS panels. The recommended budget for this activity is $65M
A Measurement of Arcminute Anisotropy in the Cosmic Microwave Background with the Sunyaev-Zel'dovich Array
We present 30 GHz measurements of the angular power spectrum of the cosmic
microwave background (CMB) obtained with the Sunyaev-Zel'dovich Array. The
measurements are sensitive to arcminute angular scales, where secondary
anisotropy from the Sunyaev-Zel'dovich effect (SZE) is expected to dominate.
For a broad bin centered at multipole 4066 we find 67+77-50 uK^2, of which
26+/-5 uK^2 is the expected contribution from primary CMB anisotropy and
80+/-54 uK^2 is the expected contribution from undetected radio sources. These
results imply an upper limit of 155 uK^2 (95% CL) on the secondary contribution
to the anisotropy in our maps. This level of SZE anisotropy power is consistent
with expectations based on recent determinations of the normalization of the
matter power spectrum, i.e., sigma_8~0.8.Comment: ApJ, 713, 82-89, (2010
Public Health Investment in Team Care: Increasing Access to Clinical Preventive Services in Los Angeles County
As part of federal and local efforts to increase access to high quality, clinical preventive services (CPS) in underserved populations, the Los Angeles County Department of Public Health (DPH) partnered with six local health system and community organization partners to promote the use of team care for CPS delivery. Although these partners were at different stages of organizational capacity, post-program review suggests that each organization advanced team care in their clinical or community environments, potentially affecting >250,000 client visits per year. Despite existing infrastructure and DPH's funding support of CPS integration, partner efforts faced several challenges. They included lack of sustainable funding for prevention services; limited access to community resources that support disease prevention; and difficulties in changing health-care provider behavior. Although team care can serve as a catalyst or vehicle for delivering CPS, downstream sustainability of this model of practice requires further state and national policy changes that prioritize prevention. Public health is well positioned to facilitate these policy discussions and to assist health system and community organizations in strengthening CPS integration
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Public Health Investment in Team Care: Increasing Access to Clinical Preventive Services in Los Angeles County
As part of federal and local efforts to increase access to high quality, clinical preventive services (CPS) in underserved populations, the Los Angeles County Department of Public Health (DPH) partnered with six local health system and community organization partners to promote the use of team care for CPS delivery. Although these partners were at different stages of organizational capacity, post-program review suggests that each organization advanced team care in their clinical or community environments, potentially affecting >250,000 client visits per year. Despite existing infrastructure and DPH's funding support of CPS integration, partner efforts faced several challenges. They included lack of sustainable funding for prevention services; limited access to community resources that support disease prevention; and difficulties in changing health-care provider behavior. Although team care can serve as a catalyst or vehicle for delivering CPS, downstream sustainability of this model of practice requires further state and national policy changes that prioritize prevention. Public health is well positioned to facilitate these policy discussions and to assist health system and community organizations in strengthening CPS integration
Public Health Investment in Team Care: Increasing Access to Clinical Preventive Services in Los Angeles County
As part of federal and local efforts to increase access to high quality, clinical preventive services (CPS) in underserved populations, the Los Angeles County Department of Public Health (DPH) partnered with six local health system and community organization partners to promote the use of team care for CPS delivery. Although these partners were at different stages of organizational capacity, post-program review suggests that each organization advanced team care in their clinical or community environments, potentially affecting >250,000 client visits per year. Despite existing infrastructure and DPH’s funding support of CPS integration, partner efforts faced several challenges. They included lack of sustainable funding for prevention services; limited access to community resources that support disease prevention; and difficulties in changing health-care provider behavior. Although team care can serve as a catalyst or vehicle for delivering CPS, downstream sustainability of this model of practice requires further state and national policy changes that prioritize prevention. Public health is well positioned to facilitate these policy discussions and to assist health system and community organizations in strengthening CPS integration
Spectroscopic follow-up of a cluster candidate at z = 1.45
The definitive version is available at www.blackwell-synergy.com. Copyright Blackwell Publishing DOI :10.1111/j.1365-2966.2007.12433.xPeer reviewe