We present multiwavelength, high spatial resolution imaging of the IRS 7 region in the R Corona Australis molecular cloud. Our observations include 1.1 mm continuum and HCO + J ¼ 3 ! 2 images from the Submillimeter Array (SMA), 12 CO J ¼ 3 ! 2 outflow maps from the DesertStar heterodyne array receiver on the Heinrich Hertz Telescope (HHT), 450 and 850 m continuum images from SCUBA, and archival Spitzer IRAC and MIPS 24 m images. The accurate astrometry of the IRAC images allow us to identify IRS 7 with the centimeter source VLA 10W (IRS 7A) and the X-ray source X W . The SMA 1.1 mm image reveals two compact continuum sources that are also distinguishable at 450 m. SMA 1 coincides with X-ray source CXOU J190156.4À365728 and VLA centimeter source 10E (IRS 7B) and is seen in the IRAC and MIPS images. SMA 2 has no infrared counterpart but coincides with centimeter source VLA 9. Spectral energy distributions constructed from SMA, SCUBA, and Spitzer data yield bolometric temperatures of 83 K for SMA 1 and 70 K for SMA 2. These temperatures along with the submillimeter to total luminosity ratios indicate that SMA 2 is a Class 0 protostar, while SMA 1 is a Class 0/Class I transitional object (L ¼ 17 AE 6 L ). The 12 CO J ¼ 3 ! 2 outflow map shows one major and possibly several smaller outflows centered on the IRS 7 region, with masses and energetics consistent with previous work. We identify the Class 0 source SMA 2/ VLA 9 as the main driver of this outflow. The complex and clumpy spatial and velocity distribution of the HCO + J ¼ 3 ! 2 emission is not consistent with either bulk rotation, or any known molecular outflow activity.
We use the CO band at 2.3 µm to constrain the populations of young stars in the central regions of Seyfert galaxies. We report new CO band spectroscopy of 46 Seyfert galaxies. In most cases, the observed CO indices appear diluted by the presence of a non-stellar component (most likely, warm dust surrounding the active nucleus). We used JHKL aperture photometry to estimate the non-stellar contribution at 2.3µm. We successfully corrected the CO band for the dilution for 16 galaxies which were not dominated by the non-stellar component. Comparing with CO indices measured in elliptical and purely starbursting galaxies, we find no evidence for strong starbursts in the majority of these galaxies.d Signal-to-nise ratio per pixel; averaged over the entire spectral range. e Anguar size of the spectral aperture, i.e. the width of the slit x the width of the extracted one-dimensional spectrum.
The role of star formation in luminous and ultraluminous infrared galaxies (LIRGs, L IR ! 10 11 L ; ULIRGs, L IR ! 10 12 L ) is a hotly debated issue: while it is clear that starbursts play a large role in powering the IR luminosity in these galaxies, the relative importance of possible enshrouded AGNs is unknown. It is therefore important to better understand the role of star-forming gas in contributing to the infrared luminosity in IR-bright galaxies. The J ¼ 3 level of 12 CO lies 33 K above ground and has a critical density of $1:5 ; 10 4 cm À3 . The 12 CO J ¼ 3 2 line serves as an effective tracer for warm, dense molecular gas heated by active star formation. Here we report on 12 CO J ¼ 3 2 observations of 17 starburst spiral galaxies, LIRGs, and ULIRGs, which we obtained with the Heinrich Hertz Submillimeter Telescope on Mount Graham, Arizona. Our main results are as follows. (1) We find a nearly linear relation between the infrared luminosity and warm, dense molecular gas such that the infrared luminosity increases as the warm, dense molecular gas to the power 0.92; we interpret this to be roughly consistent with the recent results of Gao & Solomon. (2) We find L IR /M H 2 warm; dense ratios ranging from $38 to $482 L /M using a modified CO-H 2 conversion factor of 8:3 ; 10 19 cm À2 (K km s À1 ) À1 derived in this paper.
We demonstrate photon-noise limited performance at sub-millimeter wavelengths in feedhorn-coupled, microwave kinetic inductance detectors (MKIDs) made of a TiN/Ti/TiN trilayer superconducting film, tuned to have a transition temperature of 1.4 K. Micro-machining of the silicon-on-insulator wafer backside creates a quarter-wavelength backshort optimized for efficient coupling at 250 µm. Using frequency read out and when viewing a variable temperature blackbody source, we measure device noise consistent with photon noise when the incident optical power is > 0.5 pW, corresponding to noise equivalent powers > 3×10 −17 W/ √ Hz. This sensitivity makes these devices suitable for broadband photometric applications at these wavelengths.
Using a combination of data from the Antarctic Submillimeter Telescope and Remote Observatory (AST/ RO), the Arizona Radio Observatory Kitt Peak 12 m telescope, and the Arizona Radio Observatory 10 m Heinrich Hertz Telescope, we have studied the most active part of the R CrA molecular cloud in multiple transitions of carbon monoxide, HCO + , and 870 m continuum emission. Since R CrA is nearby (130 pc), we are able to obtain physical spatial resolution as high as 0.01 pc over an area of 0.16 pc 2 , with velocity resolution finer than 1 km s À1 . Mass estimates of the protostar driving the millimeter-wave emission derived from HCO + , dust continuum emission, and kinematic techniques point to a young, deeply embedded protostar of $0.5-0.75 M , with a gaseous envelope of similar mass. A molecular outflow is driven by this source that also contains at least 0.8 M of molecular gas with $0.5 L of mechanical luminosity. HCO + lines show the kinematic signature of infall motions, as well as bulk rotation. The source is most likely a Class 0 protostellar object not yet visible at near-IR wavelengths. With the combination of spatial and spectral resolution in our data set, we are able to disentangle the effects of infall, rotation, and outflow toward this young object.
The Balloon-borne Large Aperture Submillimeter Telescope for Polarimetry (BLASTPol) was a suborbital experiment designed to map magnetic fields in order to study their role in star formation processes. BLASTPol made detailed polarization maps of a number of molecular clouds during its successful flights from Antarctica in 2010 and 2012. We present the next-generation BLASTPol instrument (BLAST-TNG) that will build off the success of the previous experiment and continue its role as a unique instrument and a test bed for new technologies. With a 16-fold increase in mapping speed, BLAST-TNG will make larger and deeper maps. Major improvements include a 2.5 m carbon fiber mirror that is 40% wider than the BLASTPol mirror and ~3000 polarization sensitive detectors. BLAST-TNG will observe in three bands at 250, 350, and 500 microns. The telescope will serve as a pathfinder project for microwave kinetic inductance detector (MKID) technology, as applied to feedhorn coupled submillimeter detector arrays. The liquid helium cooled cryostat will have a 28-day hold time and will utilize a closed-cycle $^3$He refrigerator to cool the detector arrays to 270 mK. This will enable a detailed mapping of more targets with higher polarization resolution than any other submillimeter experiment to date. BLAST-TNG will also be the first balloon-borne telescope to offer shared risk observing time to the community. This paper outlines the motivation for the project and the instrumental design
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