The Balloon-borne Large Aperture Submillimeter Telescope: BLAST

The Balloon-borne Large Aperture Submillimeter Telescope (BLAST) is a sub-orbital surveying experiment designed to study the evolutionary history and processes of star formation in local galaxies (including the Milky Way) and galaxies at cosmological distances. The BLAST continuum camera, which consists of 270 detectors distributed between 3 arrays, observes simultaneously in broad-band (30%) spectral-windows at 250, 350, and 500 microns. The optical design is based on a 2m diameter telescope, providing a diffraction-limited resolution of 30" at 250 microns. The gondola pointing system enables raster mapping of arbitrary geometry, with a repeatable positional accuracy of ~30"; post-flight pointing reconstruction to ~5" rms is achieved. The on-board telescope control software permits autonomous execution of a pre-selected set of maps, with the option of manual override. In this paper we describe the primary characteristics and measured in-flight performance of BLAST. BLAST performed a test-flight in 2003 and has since made two scientifically productive long-duration balloon flights: a 100-hour flight from ESRANGE (Kiruna), Sweden to Victoria Island, northern Canada in June 2005; and a 250-hour, circumpolar-flight from McMurdo Station, Antarctica, in December 2006.Comment: 38 Pages, 11 figures; Replaced with version accepted for publication in the Astrophysical Journal; related results available at http://blastexperiment.info

Movable genetic elements and antibiotic resistance in enterococci

The enterococci possess genetic elements able to move from one strain to another via conjugation. Certain enterococcal plasmids exhibit a broad host range among gram-positive bacteria, but only when matings are performed on solid surfaces. Other plasmids are more specific to enterococci, transfer efficiently in broth, and encode a response to recipient-produced sex phermones. Transmissible non-plasmid elements, the conjugative transposons, are widespread among the enterococci and determine their own fertility properties. Drug resistance, hemolysin, and bacteriocin determinants are commonly found on the various transmissible enterococcal elements. Examples of the different systems are discussed in this review.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47900/1/10096_2005_Article_BF01963632.pd

BOLOCAM: A 144 element bolometer array camera for millimeter-wave imaging

Large format arrays of bolometers at millimeter and submillimeter wavelengths have already begun to make an impact in studies of star formation and galaxy evolution and of the cosmic microwave background. I describe progress in the fabrication and integration of a monolithic array of 144 bolometers in a millimeter-wave camera, BOLOCAM. BOLOCAM incorporates advances in bolometer fabrication, coupling optics, cryogenics and readout electronics and provides a test-bed of these technologies for future space missions (PLANCK, FIRST). I describe the results of tests of a prototype 24 channel system and the projected sensitivity and mapping speed of the full system integrated on the Caltech Submillimeter Observatory and LMT/GTM

Cooling bolocam, a new camera for the future GTM/LMT

The observations at millimeter wavelength begin to occupy an important role in the modern astronomy. The fast growing up of millimeter--wave bolometer array systems, such as SCUBA on the JCMT, MPfIR on the IRAM telescope or SuZIE on the CSO, have opened a new window that have allowed astronomers to make significant contributions in such diverse fields as the study of primeval galaxies and the early universe, anisotropies in the CMB due to the Sunyaev-Zel'dovich effect and protostars located inside dense molecular clouds. Bolocam is a new millimeter--wave camera with 144 pixels. It will operate at wave lengths centered at 1.1, 1.4 and 2.1 mm with a spatial resolution of 43'' ($\lambda =$1.4~mm) at CSO telescope and 8'' at the LMT/GMT. This camera will have a mapping speed two orders of magnitude larger than any of the previous mentioned cameras. The sensitivity of Bolocam is determined by the cryogenic system. This poster describes the actual stage of the cryogenic system which will cool the Bolocam receivers down to 300mK

Cooling bolocam, a new camera for the future GTM/LMT

The observations at millimeter wavelength begin to occupy an important role in the modern astronomy. The fast growing up of millimeter--wave bolometer array systems, such as SCUBA on the JCMT, MPfIR on the IRAM telescope or SuZIE on the CSO, have opened a new window that have allowed astronomers to make significant contributions in such diverse fields as the study of primeval galaxies and the early universe, anisotropies in the CMB due to the Sunyaev-Zel'dovich effect and protostars located inside dense molecular clouds. Bolocam is a new millimeter--wave camera with 144 pixels. It will operate at wave lengths centered at 1.1, 1.4 and 2.1 mm with a spatial resolution of 43'' ($\lambda =$1.4~mm) at CSO telescope and 8'' at the LMT/GMT. This camera will have a mapping speed two orders of magnitude larger than any of the previous mentioned cameras. The sensitivity of Bolocam is determined by the cryogenic system. This poster describes the actual stage of the cryogenic system which will cool the Bolocam receivers down to 300mK