Intense molecular emission from the Lagoon nebula, M8

The discovery is reported of the second strongest source of mm and submm wavelength CO line emission, towards M8, the Lagoon Nebula in Sagittarius. The ~31 M⊙ molecular core has dimensions ~0.2 x 0.3pc and is centred on the O7V star Herschel 36 (H36), near the Hourglass Nebula in the core of M8. Emission from the CO line wings extends to the north and south of the Hourglass, although a lack of near-IR H2 emission indicates that outflow activity is much less prominent than in many active star-formation regions, and suggests that the CO line wings may trace the expanding edge of a cavity around H36. The molecular line data are compared with new near-IR narrow-band, continuum-subtracted images in He I, H2, and H,+ (Brγ) lines and archival HST emission-line images in Hα, [O III], and [S II]. The optical and near-IR data are found to be broadly consistent with previous photo-ionisation models of the Hourglass, which is excited by H 36. However, there are variations in the He I/Brγ line ratio which are difficult to explain

The FIRST-2MASS Red Quasar Survey

Combining radio observations with optical and infrared color selection -- demonstrated in our pilot study to be an efficient selection algorithm for finding red quasars -- we have obtained optical and infrared spectroscopy for 120 objects in a complete sample of 156 candidates from a sky area of 2716 square degrees. Consistent with our initial results, we find our selection criteria -- J-K>1.7, R-K>4.0 -- yield a ~50% success rate for discovering quasars substantially redder than those found in optical surveys. Comparison with UVX- and optical color-selected samples shows that >~ 10% of the quasars are missed in a magnitude-limited survey. Simultaneous two-frequency radio observations for part of the sample indicate that a synchrotron continuum component is ruled out as a significant contributor to reddening the quasars' spectra. We go on to estimate extinctions for our objects assuming their red colors are caused by dust. Continuum fits and Balmer decrements suggest E(B-V) values ranging from near zero to 2.5 magnitudes. Correcting the K-band magnitudes for these extinctions, we find that for K <= 14.0, red quasars make up between 25% and 60% of the underlying quasar population; owing to the incompleteness of the 2MASS survey at fainter K-band magnitudes, we can only set a lower limit to the radio-detected red quasar population of >20-30%.Comment: 80 pages (single-column, preprint format) 20 figures, Accepted for publicated in Ap

High resolution molecular line observations of the Serpens Nebula

The Serpens Molecular cloud is a nearby low/intermediate mass star forming region that is in the final stages of forming a densely packed cluster of stars. Spectra and high angular resolution maps of the CO, 13CO, C18O and C17O J=2-1 and CO J=4-3 transitions were obtained to study the distribution of molecular gas near the cluster. These are supplemented with data on the J=4-3 HCO+ line (to probe the denser gas), and 3P1 - 3P0 line of atomic carbon. The mass of the region is estimated to be ~1450Msun, implying that the star formation efficiency in the region to date has been ~2.5percent. Several molecular outflows are visible in the maps; some are associated with compact objects visible in millimetre and submillimetre wave continuum maps, as well as more widespread diffuse high velocity gas that extends over much of the nebula. The mass and energy of material in the high velocity gas are relatively small, ~0.3Msun and 3 x 1045 erg s-1, consistent with the characteristics of outflows seen towards low mass star-formation regions. The directions of the overlapping outflow lobes do not however show a clear alignment with the cloud's large scale magnetic field as has been reported towards some other regions. The gas temperatures in the central part of the molecular cloud are warmer (~30-40K) than typical for dark clouds, suggesting that the Serpens cluster has interacted with, and heated this gas. Estimates of the CO isotopomeric abundance ratios from these data may be strongly affected by opacity and radiative transfer effects. In a comparison of the LTE and LVG techniques, the disagreement between the derived column densities is discussed - with particular relevance to the higher rotationa

Dedicated outreach service for hard to reach patients with tuberculosis in London: observational study and economic evaluation.

OBJECTIVE: To assess the cost effectiveness of the Find and Treat service for diagnosing and managing hard to reach individuals with active tuberculosis. DESIGN: Economic evaluation using a discrete, multiple age cohort, compartmental model of treated and untreated cases of active tuberculosis. SETTING: London, United Kingdom. Population Hard to reach individuals with active pulmonary tuberculosis screened or managed by the Find and Treat service (48 mobile screening unit cases, 188 cases referred for case management support, and 180 cases referred for loss to follow-up), and 252 passively presenting controls from London's enhanced tuberculosis surveillance system. MAIN OUTCOME MEASURES: Incremental costs, quality adjusted life years (QALYs), and cost effectiveness ratios for the Find and Treat service. RESULTS: The model estimated that, on average, the Find and Treat service identifies 16 and manages 123 active cases of tuberculosis each year in hard to reach groups in London. The service has a net cost of £1.4 million/year and, under conservative assumptions, gains 220 QALYs. The incremental cost effectiveness ratio was £6400-£10,000/QALY gained (about €7300-€11,000 or $10,000-$16 000 in September 2011). The two Find and Treat components were also cost effective, even in unfavourable scenarios (mobile screening unit (for undiagnosed cases), £18,000-£26,000/QALY gained; case management support team, £4100-£6800/QALY gained). CONCLUSIONS: Both the screening and case management components of the Find and Treat service are likely to be cost effective in London. The cost effectiveness of the mobile screening unit in particular could be even greater than estimated, in view of the secondary effects of infection transmission and development of antibiotic resistance