First Results from SPARO: Evidence for Large-Scale Toroidal Magnetic Fields in the Galactic Center

We have observed the linear polarization of 450 micron continuum emission from the Galactic center, using a new polarimetric detector system that is operated on a 2 m telescope at the South Pole. The resulting polarization map extends ~ 170 pc along the Galactic plane and ~ 30 pc in Galactic latitude, and thus covers a significant fraction of the central molecular zone. Our map shows that this region is permeated by large-scale toroidal magnetic fields. We consider our results together with radio observations that show evidence for poloidal fields in the Galactic center, and with Faraday rotation observations. We compare all of these observations with the predictions of a magnetodynamic model for the Galactic center that was proposed in order to explain the Galactic Center Radio Lobe as a magnetically driven gas outflow. We conclude that the observations are basically consistent with the model.Comment: 11 pages, 2 figures, 1 table, submitted to ApJ Let

First Results from Viper: Detection of Small-Scale Anisotropy at 40 GHZ

Results of a search for small-scale anisotropy in the cosmic microwave background (CMB) are presented. Observations were made at the South Pole using the Viper telescope, with a .26 degree (FWHM) beam and a passband centered at 40 GHz. Anisotropy band-power measurements in bands centered at l = 108, 173, 237, 263, 422 and 589 are reported. Statistically significant anisotropy is detected in all bands.Comment: 5 pages, 4 figures, uses emulateapj.sty, submitted to ApJ Letter

Hardware test program for evaluation of baseline range/range rate sensor concept

The test program Phase II effort provides additional design information in terms of range and range rate (R/R) sensor performance when observing and tracking a typical spacecraft target. The target used in the test program was a one-third scale model of the Hubble Space Telescope (HST) available at the MSFC test site where the tests were performed. A modified Bendix millimeter wave radar served as the R/R sensor test bed for evaluation of range and range rate tracking performance, and generation of radar signature characteristics of the spacecraft target. A summary of program test results and conclusions are presented along with detailed description of the Bendix test bed radar with accompaning instrumentation. The MSFC test site and facilities are described. The test procedures used to establish background levels, and the calibration procedures used in the range accuracy tests and RCS (radar cross section) signature measurements, are presented and a condensed version of the daily log kept during the 5 September through 17 September test period is also presented. The test program results are given starting with the RCS signature measurements, then continuing with range measurement accuracy test results and finally the range and range rate tracking accuracy test results

Measurement of the inclusive energy spectrum in the very forward direction in proton-proton collisions at root s=13 TeV

Peer reviewe

Background-Limited Performance in the Submillimeter

We have been awarded NASA funds to construct a Submillimeter (SMM) Array Photometer for use at the Caltech SMM Observatory (CSO) on Mauna Kea. The array will consist of 5×5 composite bolometers illuminated through light cones. On the CSO, each cone will cover 25 arcsecs on the sky, implying a total field-of-view for the array of just over 2×2 arcmins. Our aim is to achieve background-limited performance in the 730 and 870 μm atmospheric windows, thus obtaining a Noise Equivalent Flux Density (NEFD) of approximately 0.1 Jy/√Hz at these wavelengths. This sensitivity level will enable 5-sigma measurements of 10 mJy sources (such as radio-quiet quasars) in about one hour. We also will have the capability to operate at 1.1 mm, but the photometer will not be optimized at this wavelength. This system is expected to be operational on the CSO in January 1994.</jats:p