Balloon-Borne Video Cassette Recorders For Digital Data Storage

A high-speed, high-capacity digital data storage system has been developed for a new balloon-borne gamma-ray telescope {see paper 0G9.2-2). The system incorporates sophisticated, yet easy to use and economical consumer products: the portable video cassette recorder (VCR) and a relatively newer item - the "digital audio processor". The in-flight recording system employs eight VCRs and will provide a continuous data storage rate of 1.4 megabits/sec throughout a 40 hour balloon flight. Data storage capacity is 25 gigabytes and power consumption is only 10 watts

A balloon-borne imaging gamma-ray telescope

A balloon-borne coded-aperture gamma-ray telescope for galactic and extragalactic astronomy observations is described. The instrument, called Gamma Ray Imaging Payload (GRIP), is designed for measurements in the energy range from 30 keV to 5 MeV with an angular resolution of 0.6 deg over a 20 deg field of view. Distinguishing characteristics of the telescope are a rotating hexagonal coded-aperture mask and a thick NaI scintillation camera. Rotating hexagonal coded-apertures and the development of thick scintillation cameras are discussed

First Flight of a New Balloon-Borne Gamma-Ray Imaging Telescope

The first flight of a new balloon-borne gamma-ray imaging payload (GRIP) occurred on Oct. 15 and 16, 1986 from Palestine, Texas. Observations included the quasar 3C273, the galactic center, and the Crab and Cygnus regions. We discuss the instrument performance and present images of the Crab and Cygnus regions with 0.6 degree resolution over a 20 degree field of view

A Cosmic Ray Isotope Spectrometer

We describe a new instrument to be flown on ISEE-C which is optimized to measure the isotopic composition of solar and galactic cosmic rays with ~5 to ~250 MeV/nucleon. A mass resolution of ≾ 0.3 AMU should be achieved for all elements with charge Z ≤ 30

A Balloon-Borne Imaging Gamma-Ray Telescope

This paper describes a balloon-borne coded-aperture y-ray telescope for galactic and extragalactic astronomy observations. The instrument, called GRIP (Gamma Ray Imaging Payload), is designed for measurements in the energy range from 30 keV to 5 MeV with an angular resolution of 0.6° over a 20° field of view. Distinguishing characteristics of the telescope are a rotating hexagonal coded-aperture mask and a thick NaI scintillation camera. Rotating hexagonal coded-apertures and the development of thick scintillation cameras are discussed in Cook et al. [1984 and 1985, referred to as Papers I and II respectively]

The Voyager Cosmic Ray Experiment

The Voyager Cosmic Ray Experiment includes seven dE/dx- E telescopes to measure the energy and charge of particles of 1 ≤ Z ≤ 26 in the energy range 1-500 MeV/ nucleon and to measure electron energy in the range 3 ≤ E_e ≤ 110 MeV. Isotopic composition of hydrogen through sulfur in the range up to 75 MeV/nucleon can also be resolved. The electronic systems include a dual-gain, charge sensitive preamplifier, 4096-channel pulse height analyzers for three parameter analysis of selected events, and an event type readout polling scheme to maximize the use of available telemetry space and to enhance the occurrence of rare events in the data. Details of the detector, electronic and mechanical design are presented

Supernova / Acceleration Probe: A Satellite Experiment to Study the Nature of the Dark Energy

The Supernova / Acceleration Probe (SNAP) is a proposed space-based experiment designed to study the dark energy and alternative explanations of the acceleration of the Universe's expansion by performing a series of complementary systematics-controlled measurements. We describe a self-consistent reference mission design for building a Type Ia supernova Hubble diagram and for performing a wide-area weak gravitational lensing study. A 2-m wide-field telescope feeds a focal plane consisting of a 0.7 square-degree imager tiled with equal areas of optical CCDs and near infrared sensors, and a high-efficiency low-resolution integral field spectrograph. The SNAP mission will obtain high-signal-to-noise calibrated light-curves and spectra for several thousand supernovae at redshifts between z=0.1 and 1.7. A wide-field survey covering one thousand square degrees resolves ~100 galaxies per square arcminute. If we assume we live in a cosmological-constant-dominated Universe, the matter density, dark energy density, and flatness of space can all be measured with SNAP supernova and weak-lensing measurements to a systematics-limited accuracy of 1%. For a flat universe, the density-to-pressure ratio of dark energy can be similarly measured to 5% for the present value w0 and ~0.1 for the time variation w'. The large survey area, depth, spatial resolution, time-sampling, and nine-band optical to NIR photometry will support additional independent and/or complementary dark-energy measurement approaches as well as a broad range of auxiliary science programs. (Abridged)Comment: 40 pages, 18 figures, submitted to PASP, http://snap.lbl.go