摘要:

We have investigated numerically the effect of varying BATSE trigger parameters on the modeled BATSE detection rate. We have quantified the systematic effects generated by the complex interplay of the trigger times, variations in the signal‐to‐noise ratio for burst detection as well as the time scale over which backgrounds are determined, and the number of required detections above threshold. Our study employed measured background rates in large area detectors (LAD) for the day July 4, 1991. Earth blockage has been included. To model burst temporal profiles we used a sample of digitized Konus1profiles for the 50 most intense bursts detected by Venera 11 and 12. Our present, somewhat preliminary study demonstrates that, first, employing a third detection, at a reduced signal‐to‐noise ratio, to resolve a burst does not increase the detection rate, and second, the BATSE detection rate is quite insensitive to variations in the time scale over which the background is determined.

ISSN:0094-243X    

DOI:10.1063/1.42767

出版商:AIP    

年代:1991

数据来源: AIP

摘要:

The goal of the Germanium GAlactic Plane Patrol mission (GGAPP) is to provide a continuous monitor of the Galactic Plane (GP) for variable sources of gamma‐ray lines. Potentially interesting sources include black hole candidates, x‐ray binary systems, pulsars, gamma‐ray bursts, and solar flares. The GGAPP instrument is an array of Ge detectors cooled by a mechanical refrigerator to achieve a spectral resolution of 2 keV at 1 MeV (1/500). A bismuth germanate (BGO) shield will restrict the field‐of‐view (FOV) to within 20° of the GP and a modulation collimator system will locate strong sources to <0.3° in galactic longitude, provide a direct means of subtracting background, and mapping the diffuse emission from the GP. The spacecraft will be rotationally stabilized with the spin axis perpendicular to the GP such that the modulator scans in galactic longitude. A HEO or L1 orbit will keep GGAPP far away from the strong background produced by the Earth. GGAPP will provide a natural bridge between GRO and future missions such as INTEGRAL/NAE.

ISSN:0094-243X    

DOI:10.1063/1.42769

出版商:AIP    

年代:1991

数据来源: AIP

摘要:

Preliminary results pertaining to burst location using BATSE large Area Detector measurements of solar flares are presented. These solar flare measurements are currently being used to fine tune the calibration of our data analysis software. The current status of techniques for identifying and eliminating systematic errors from the data analysis tools is discussed. Data revealing the effects of the atmospheric scattering algorithm that will be implemented in the data analysis software are presented.

ISSN:0094-243X    

DOI:10.1063/1.42770

出版商:AIP    

年代:1991

数据来源: AIP

摘要:

The Burst and Transient Source Experiment (BATSE) detects any &ggr;‐ray burst not obscured by the earth and intense enough to produce a sufficiently strong signal in at least two of its eight large area NaI detectors (LADs). For a given intensity, a LAD records a stronger signal from a source which directly faces it than from a source to its side. Thus, BATSE’s detection of a &ggr;‐ray burst may depend upon the burst’s direction. We discuss the effect of this uneven exposure to the sky on the instrument’s measurement of the distribution of &ggr;‐ray burst directions and intensities, and we describe our method of accounting for the effect.

ISSN:0094-243X    

DOI:10.1063/1.42771

出版商:AIP    

年代:1991

数据来源: AIP

摘要:

The Explosive Transient Camera (ETC) is a wide‐field sky monitor capable of detecting short‐timescale optical transients. The ETC is a completely automatic instrument which executes its observing program year‐round with minimal human intervention. In this paper, we review the current status of the ETC.

ISSN:0094-243X    

DOI:10.1063/1.42773

出版商:AIP    

年代:1991

数据来源: AIP

摘要:

The mystery of the origin of gamma bursters has recently been compounded by the data from BATSE on the Gamma Ray Observatory (GRO) reporting on 132 bursters.1At present there seems to be no simple model that explains these bursts. In some processes (primordial black holes and cosmic strings) one expects a neutrino burst of even greater intensity and energy than the &ggr;‐rays. However, current theory does not predict large enough numbers of such sources; we therefore assume the &ggr;‐ray bursts give the primary source numbers and indicate the size of detector required to detect such a neutrino burst. The recently proposed SNBO detector (Phase 1, 106tons) might be a candidate to carry out this search.

ISSN:0094-243X    

DOI:10.1063/1.42774

出版商:AIP    

年代:1991

数据来源: AIP

ISSN:0094-243X    

DOI:10.1063/1.42775

出版商:AIP    

年代:1991

数据来源: AIP