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We present new cosmic microwave background (CMB) anisotropy results from the combined analysis of the three flights of the first Medium Scale Anisotropy Measurement (MSAM1). This balloon-borne bolometric instrument measured about 10 square degrees of sky at half-degree resolution in 4 frequency bands from 5.2 icm to 20 icm with a high signal-to-noise ratio. Here we present an overview of our analysis methods, compare the results from the three flights, derive new constraints on the CMB power spectrum from the combined data and reduce the data to total-power Wiener-filtered maps of the CMB. A key feature of this new analysis is a determination of the amplitude of CMB fluctuations at $\ell \sim 400$. The analysis technique is described in a companion paper by Knox.

The third flight of the Medium-Scale Anisotropy Measurement (MSAM1), in 1995 June, observed a new strip of sky, doubling the sky coverage of the original MSAM1 data set. MSAM1 observes with a 05 beam size in four bands from 5 to 20 cm-1. From these four bands we derive measurements of cosmic microwave background radiation (CMBR) anisotropy and interstellar dust emission. Our measurement of dust emission correlates well with the 100 μm IRAS Sky Survey Atlas; from this comparison we determine an effective emissivity spectral index between 100 μm and 444 μm of 1.46±0.28. Analysis of our measurement of CMBR anisotropy shows that for Gaussian-shaped correlation functions with θc = 03, we place a limit on total rms anisotropy of 2.2×10−5

Whole disk brightness ratios for Jupiter, Saturn, and Mars are reported at 5.7, 9.5, 16.4, and 22.5 cm$^{-1}$. Using models for the brightness temperature of Mars, the whole disk brightness temperatures for Jupiter and Saturn are also given for the four frequencies., 13 pages, LaTeX+aasms4 package, 2 included PostScript figures. Submitted to Ap.J Letters

The goal of the second flight of the medium-scale anisotropy measurement (MSAM1-94) was to confirm the measurement of cosmic microwave background radiation (CMBR) anisotropy made in the first flight (MSAM1-92). The CMBR anisotropy and interstellar dust emission signals from the two flights are compared by forming the sum and difference of those portions of the data with the same pointings on the sky. The difference data are consistent with a null detection, while the summed data show significant signal. We conclude that MSAM1-92 and MSAM1-94 measured the same celestial signal.

Using a silicon-microstrip detector array to identify secondary vertices, we have observed {ital b}{r_arrow}{ital J}/{psi}{r_arrow}{mu}{sup +}{mu}{sup {minus}} decays in 800 GeV/{ital c} proton-gold interactions. The doubly differential cross section for {ital J}/{psi} mesons originating from {ital b}-quark decays, assuming linear dependence on nucleon number, is {ital d}{sup 2}{sigma}/{ital dx}{sub {ital Fdp}}{sup 2}{sub {ital T}}=107{plus_minus}28{plus_minus}19/nucleon at {ital x}{sub {ital F}}=0.05 and {ital p}{sub {ital T}}=1GeV/{ital c}. This measurement is compared to next-to-leading-order QCD predictions. The integrated {ital b}-quark production cross section, obtained by extrapolation over all {ital x}{sub {ital F}} and {ital p}{sub {ital T}}, is {sigma}({ital pN}{r_arrow}{ital bb}{ovr bar}+{ital X})=5.7{plus_minus}1.5{plus_minus}1.3 nb/nucleon.

The differential cross sections do/dxF for J/G produced inclusively in 800 GeV/c p-Cn and pBe collisions have been measured in the kinematic range 0.30 5 IF < 0.95 through the decay mode J/G + p+p-. They are compared with the predictions of the semilocal duality model for several sets of parton density functions. No evidence for a suggested intrinsic charm contribution to the cross section is observed. The ratio of the differential cross sections for Cu and Be targets confirms the suppression of J/$ production in heavy nuclei at large ZF.

A Silicon Microstrip Spectrometer has been installed and successfully operated in experiment E789 at Fermilab. The main physics goal of the experiment is to search for charged particle decays of B and D Mesons. Damage effects due to ionizing radiation exposure to the silicon during the experiment are reported.

Results of a search for the three neutral charm decays, D0 -> mu e, D0 -> mu mu, and D0 -> e e, are presented. This study was based on data collected in Experiment 789 at the Fermi National Accelerator Laboratory using 800 GeV/c proton-Au and proton-Be interactions. No evidence is found for any of the decays. Upper limits on the branching ratios, at the 90% confidence level, are obtained., 28 pages, 18 figures. Submitted to Physical Review D

We present a measurement of the W-to-Be per-nucleon cross-section ratio, ${\mathit{R}}_{\mathrm{W}/\mathrm{B}\mathrm{e}}$, for single hadrons and for opposite-sign hadron pairs produced in p-A collisions at \ensuremath{\surd}s=38.8 GeV. The data fill in regions of intermediate transverse momentum and dihadron mass that previously have revealed cross-section enhancements for scattering from nuclear targets. When combined with previous measurements, the new results help delineate the dependence of nuclear effects on the kinematic variables ${\mathit{p}}_{\mathit{t}}$, m, and \ensuremath{\surd}s. Both the single-hadron and hadron-pair enhancements in ${\mathit{R}}_{\mathrm{W}/\mathrm{B}\mathrm{e}}$ seen at intermediate values of ${\mathit{p}}_{\mathit{t}}$ and mass decrease with increasing \ensuremath{\surd}s, consistent with a multiple-scattering model of parton scattering. \textcopyright{} 1996 The American Physical Society.

We report the characterization of bright, compact features in the cosmic microwave background radiation (CMBR) detected during the June 1992 and June 1994 balloon flights of the Medium Scale Anisotropy Measurement (MSAM1-92 and MSAM1-94, respectively). Spectral flux densities are determined for each feature at 5.7, 9.3, and 16.5 cm$^{-1}$. No viable counterparts for these features were found in source catalogs at 5 GHz or at 100 $\mu$m. The measured spectrum of each feature is consistent with a temperature fluctuation in the CMBR. The existence of these features is consistent with adiabatic fluctuation models of anisotropy in the CMBR., Comment: 17 pages, LaTeX+aasms4 package, 2 included PostScript figures. Submitted to Ap.J Letters

Observations from the first flight of the Medium Scale Anisotropy Measurement (MSAM1-92) are analyzed to search for the Sunyaev-Zel'dovich (SZ) effect towards the Coma cluster. This balloon-borne instrument uses a $28\arcmin$ FWHM beam and a three position chopping pattern with a throw of $\pm40\arcmin$. With spectral channels at 5.7, 9.3, 16.5, and 22.6~\icm, the observations simultaneously sample the frequency range where the SZ spectral distortion in the intensity transitions from a decrement to an increment and where the fractional intensity change is substantially larger than in the Rayleigh-Jeans region. We set limits on the Comptonization parameter integrated over our antenna pattern, $\Delta y \leq 8.0 \times 10^{-5}$($2 \sigma$). For a spherically symmetric isothermal model, this implies a central Comptonization parameter, $y_o \leq 2.0 \times 10^{-4}$, or a central electron density, $n_o \leq 5.8 \times10^{-3}$cm$^{-3}h_{50}$, a result consistent with central densities implied by X-ray brightness measurements and central Comptonization estimates from lower frequency observations of the SZ effect., Comment: 11 pages, LaTeX+aasms4 package, 1 PostScript figure. Submitted to Ap.J Letters

The second flight of the Medium Scale Anisotropy Measurement (MSAM1-94) observed the same field as the first flight (MSAM1-92) to confirm our earlier measurement of cosmic microwave background radiation (CMBR) anisotropy. This instrument chops a 30\arcmin\ beam in a 3 position pattern with a throw of $\pm40\arcmin$, and simultaneously measures single and double differenced sky signals. We observe in four spectral channels centered at 5.6, 9.0, 16.5, and 22.5~\icm, providing sensitivity to the peak of the CMBR and to thermal emission from interstellar dust. The dust component correlates well with the \IRAS\ 100~\micron\ map. The CMBR observations in our double difference channel correlate well with the earlier observations, but the single difference channel shows some discrepancies. We obtain a detection of fluctuations in the MSAM1-94 dataset that match CMBR in our spectral bands of $\Delta T/T = 1.9^{+1.3}_{-0.7}\times 10^{-5}$ (90\% confidence interval, including calibration uncertainty) for total rms Gaussian fluctuations with correlation angle 0\fdg3, using the double difference demodulation., Comment: 11 pages, 4 postscript figures, uses aastex 4.0. Transmitted in uuencoded gzipped tar file

With a data sample containing 1.1{times}10{sup 5} {ital J}/{psi}{r_arrow}{mu}{sup +}{mu}{sup {minus}} decays reconstructed with 16 MeV/{ital c}{sup 2} rms mass resolution, we have measured the differential cross sections versus Feynman-{ital x}, rapidity, and {ital p}{sub {ital T}} for the production of {ital J}/{psi} and {psi}{prime} in 800 GeV/{ital c} {ital p}-Au collisions. Our results are compared with leading-order QCD predictions and with previous measurements. While the shapes of the cross sections are in qualitative agreement with QCD predictions, the magnitudes disagree by factors of 7 ({ital J}/{psi}) and 25 ({psi}{prime}). Assuming an appropriate form for the differential cross sections in regions not measured we derive a total {ital J}/{psi} production cross section {sigma}({ital p}+{ital N}{r_arrow}{ital J}/{psi}+{ital X})=442{plus_minus}2{plus_minus}88 nb/nucleon and a (model-dependent) total {psi}{prime} cross secton {sigma}({ital p}+{ital N}{r_arrow}{psi}{prime}+{ital X})=75{plus_minus}5{plus_minus}22 nb/nucleon. For {ital J}/{psi} produced at central rapidity, {ital d}{sigma}({ital p}+{ital N}{r_arrow}{ital J}/{psi}+{ital X})/{ital dy}{vert_bar}{sub {ital y}=0}=230{plus_minus}5{plus_minus}46 nb/nucleon.

The nuclear dependence for 800 GeV/[ital c] proton production of neutron [ital D] mesons has been measured near [ital x][sub [ital F]]=0 in Experiment 789 at Fermilab. [ital D] mesons from beryllium and gold targets were detected with a pair spectrometer and a silicon vertex detector via their decay [ital D][r arrow][ital K][pi]. No nuclear dependence is found, with a measured [alpha]=1.02[plus minus]0.03[plus minus]0.02. The measured differential cross section, [ital d][sigma]/[ital dx][sub [ital F]], for neutral-[ital D]-meson production at [l angle][ital x][sub [ital F]][r angle]=0.031 is 58[plus minus]3[plus minus]7 [mu]b/nucleon. The integrated cross section obtained by extrapolation of the measured cross section to all [ital x][sub [ital F]] is 17.7[plus minus]0.9[plus minus]3.4 [mu]b/nucleon and is consistent with previous measurements.

Observations from the first flight of the Medium Scale Anisotropy Measurement (MSAM) are analyzed to place limits on Gaussian fluctuations in the Cosmic Microwave Background Radiation (CMBR). This instrument chops a 30\arcmin\ beam in a 3 position pattern with a throw of $\pm40\arcmin$; the resulting data is analyzed in statistically independent single and double difference datasets. We observe in four spectral channels at 5.6, 9.0, 16.5, and 22.5~\icm, allowing the separation of interstellar dust emission from CMBR fluctuations. The dust component is correlated with the \IRAS\ 100~\micron\ map. The CMBR component has two regions where the signature of an unresolved source is seen. Rejecting these two source regions, we obtain a detection of fluctuations which match CMBR in our spectral bands of $0.6 \times 10^{-5} < ��T/T < 2.2 \times 10^{-5}$ (90\% CL interval) for total rms Gaussian fluctuations with correlation angle 0\fdg5, using the single difference demodulation. For the double difference demodulation, the result is $1.1 \times 10^{-5} < ��T/T < 3.1 \times 10^{-5}$ (90\% CL interval) at a correlation angle of 0\fdg3., 13 pages + 3 figures (included), LaTeX + AASTeX v3.0

Fermilab experiment 789 studies low‐multiplicity decays of neutral D and B mesons in a high‐rate fixed‐target environment. Preliminary results from the 1991 run are presented.

We propose a concept for radiometry in the millimeter, the submillimeter, and the far-IR spectral regions, the frequency selective bolometer (FSB). This system uses a bolometer as a coupled element of a tuned quasi-optical interference filter in which the absorption, the transmission, and the reflection characteristics of the filter depend on the frequency in a controlled manner. Several FSB's can be cascaded within a straight light pipe to produce a high-efficiency, compact, multiband radiometer. A prototype design is presented together with its anticipated performance based on a one-dimensional transmission-line model. Instruments based on FSB technology should have several advantages over current multiband bolometric radiometers including smaller and more compact cryogenic optics, reduced demands on cryostat size and weight, high coupling efficiency, minimum constraints on the geometry in the focal plane. An FSB system can be configured as a multiband, close-packed focal-plane array, permitting efficient use of the throughput of a telescope.