We present the detection of infall, rotation and outflow kinematic signatures towards both a protostellar source, VLA 1623 and what was initially thought to be a pre-protostellar core, SM1N, in the ρ Ophiuchus A region. The kinematic signatures of early star formation were detected in the dense molecular gas surrounding the embedded sources using high signal-to-noise millimeter and submillimeter data. Centroid velocity maps made with HCO + J=4→3 and J=1→0 line emission exhibit the blue bulge signature of infall, which is predicted to be seen when infall motion dominates over rotational motion. Further evidence for infalling gas is found in the HCO + blue asymmetric line profiles and red asymmetric opacity profiles. We also performed CO J=3→2 and J=1→0 observations to determine the direction, orientation, and extent of molecular outflows, and report the discovery of a new bipolar outflow possibly driven by SM1N.

Frequency-selective bolometers (FSBs) are a new type of detector for millimeter and submillimeter wavelengths that are transparent to all but a narrow range of frequencies as set by characteristics of the absorber itself. Therefore stacks of FSBs tuned to different frequencies provide a low-loss compact method for utilizing a large fraction of the light collected by a telescope. Tests of prototype FSBs indicate that the absorption spectra are well predicted by models, that peak absolute absorption efficiencies of the order of 50% are attainable, and that their out-of-band transmission is high.

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We discuss the development, at Argonne National Laboratory, of a four-pixel camera suitable for photometry of distant dusty galaxies located by Spitzer and SCUBA, and for study of other millimeter-wave sources such as ultra-luminous infrared galaxies, the Sunyaev-Zeldovich (SZ) effect in clusters, and galactic dust. Utilizing Frequency Selective Bolometers (FSBs) with superconducting Transition-Edge Sensors (TESs), each of the camera's four pixels is sensitive to four colors, with frequency bands centered approximately at 150, 220, 270, and 360 GHz.The current generation of these devices utilizes proximity effect superconducting bilayers of Mo/Au or Ti/Au for TESs, along with frequency selective circuitry on membranes of silicon nitride 1 cm across and 1 micron thick. The operational properties of these devices are determined by this circuitry, along with thermal control structures etched into the membranes. These etched structures do not perforate the membrane, so that the device is both comparatively robust mechanically and carefully tailored in terms of its thermal transport properties.In this paper, we report on development of the superconducting bilayer TES technology and characterization of the FSB stacks. This includes the use of new materials, the design and testing of thermal control structures, the introduction of desirable thermal properties using buried layers of crystalline silicon underneath the membrane, detector stability control, and optical and thermal test results. The scientific motivation, FSB design, FSB fabrication, and measurement results are discussed. SCIENTIFIC MOTIVATIONMillimeter and sub-millimeter wavelength observations offer unique insights about the early universe. Recognizing this, and spurred on by the recent success of mm/sub-mm observations, the observational cosmology community is currently developing telescopes and receivers of unprecedented sensitivity and scale. Multi-frequency studies will be necessary in order to obtain spectra from sources of interest uncontaminated by background and foreground signals. Therefore, the new telescopes must possess high optical efficiencies over a wide range of wavelengths. A receiver technology which simultaneously utilizes a telescope's full light-gathering power at several distinct frequencies has a great sensitivity advantage over conventional multi-color observing schemes in which only some of the collected light or observing time is allocated to each frequency band. The Frequency Selective Bolometer (FSB) presently under prototype development at Argonne National Laboratory is just such a technology. _____________________________ Corresponding author information for A.D.: E-mail: datesman@anl.gov, Phone: 1 630 252 9154, Mail: 9700 S. Cass Ave., Argonne, IL 60439 U.S.A.

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