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Title: Developing the Galactic Diffuse Emission Model for the GLAST Large Area Telescope

Abstract

Diffuse emission is produced in energetic cosmic ray (CR) interactions, mainly protons and electrons, with the interstellar gas and radiation field and contains the information about particle spectra in distant regions of the Galaxy. It may also contain information about exotic processes such as dark matter annihilation, black hole evaporation etc. A model of the diffuse emission is important for determination of the source positions and spectra. Calculation of the Galactic diffuse continuum g-ray emission requires a model for CR propagation as the first step. Such a model is based on theory of particle transport in the interstellar medium as well as on many kinds of data provided by different experiments in Astrophysics and Particle and Nuclear Physics. Such data include: secondary particle and isotopic production cross sections, total interaction nuclear cross sections and lifetimes of radioactive species, gas mass calibrations and gas distribution in the Galaxy (H{sub 2}, H I, H II), interstellar radiation field, CR source distribution and particle spectra at the sources, magnetic field, energy losses, g-ray and synchrotron production mechanisms, and many other issues. We are continuously improving the GALPROP model and the code to keep up with a flow of new data. Improvement in anymore » field may affect the Galactic diffuse continuum g-ray emission model used as a background model by the GLAST LAT instrument. Here we report about the latest improvements of the GALPROP and the diffuse emission model.« less

Authors:
; ; ;
Publication Date:
Research Org.:
Stanford Linear Accelerator Center (SLAC)
Sponsoring Org.:
USDOE
OSTI Identifier:
903007
Report Number(s):
SLAC-PUB-12467
arXiv:0704.1328; TRN: US0703228
DOE Contract Number:
AC02-76SF00515
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
43 PARTICLE ACCELERATORS; ANNIHILATION; ASTROPHYSICS; BLACK HOLES; CROSS SECTIONS; ELECTRONS; ENERGY LOSSES; EVAPORATION; MAGNETIC FIELDS; NONLUMINOUS MATTER; NUCLEAR PHYSICS; PROTONS; RADIATIONS; SPECTRA; SYNCHROTRONS; TELESCOPES; TRANSPORT; Astrophysics,ASTRO

Citation Formats

Moskalenko, Igor V., Strong, Andrew W., Digel, Seth W., and Porter, Troy A. Developing the Galactic Diffuse Emission Model for the GLAST Large Area Telescope. United States: N. p., 2007. Web. doi:10.2172/903007.
Moskalenko, Igor V., Strong, Andrew W., Digel, Seth W., & Porter, Troy A. Developing the Galactic Diffuse Emission Model for the GLAST Large Area Telescope. United States. doi:10.2172/903007.
Moskalenko, Igor V., Strong, Andrew W., Digel, Seth W., and Porter, Troy A. Mon . "Developing the Galactic Diffuse Emission Model for the GLAST Large Area Telescope". United States. doi:10.2172/903007. https://www.osti.gov/servlets/purl/903007.
@article{osti_903007,
title = {Developing the Galactic Diffuse Emission Model for the GLAST Large Area Telescope},
author = {Moskalenko, Igor V. and Strong, Andrew W. and Digel, Seth W. and Porter, Troy A.},
abstractNote = {Diffuse emission is produced in energetic cosmic ray (CR) interactions, mainly protons and electrons, with the interstellar gas and radiation field and contains the information about particle spectra in distant regions of the Galaxy. It may also contain information about exotic processes such as dark matter annihilation, black hole evaporation etc. A model of the diffuse emission is important for determination of the source positions and spectra. Calculation of the Galactic diffuse continuum g-ray emission requires a model for CR propagation as the first step. Such a model is based on theory of particle transport in the interstellar medium as well as on many kinds of data provided by different experiments in Astrophysics and Particle and Nuclear Physics. Such data include: secondary particle and isotopic production cross sections, total interaction nuclear cross sections and lifetimes of radioactive species, gas mass calibrations and gas distribution in the Galaxy (H{sub 2}, H I, H II), interstellar radiation field, CR source distribution and particle spectra at the sources, magnetic field, energy losses, g-ray and synchrotron production mechanisms, and many other issues. We are continuously improving the GALPROP model and the code to keep up with a flow of new data. Improvement in any field may affect the Galactic diffuse continuum g-ray emission model used as a background model by the GLAST LAT instrument. Here we report about the latest improvements of the GALPROP and the diffuse emission model.},
doi = {10.2172/903007},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Mon Apr 30 00:00:00 EDT 2007},
month = {Mon Apr 30 00:00:00 EDT 2007}
}

Technical Report:

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  • The silicon tracker for the engineering model of the GLAST Large Area Telescope(LAT) has at least two unique features: it employs self triggering readout electronics, dissipating less than 200 mu-W per channel and to date represents the largest surface of silicon microstrip detectors assembled in a tracker (2.7 m{sup 2}). It demonstrates the feasibility of employing this technology for satellite based experiments, in which low power consumption, large effective areas and high reliability are required. This note describes the construction of this silicon tracker, which was installed in a beam test of positrons, hadrons and tagged photons at SLAC inmore » December of 1999 and January of 2000.« less
  • The silicon tracker for the engineering model of the GLAST Large Area Telescope(LAT) to date represents the largest surface of silicon microstrip detectors assembled in a tracker (2.7 m{sup 2}). It demonstrates the feasibility of employing this technology for satellite based experiments, in which large effective areas and high reliability are required. This note gives an overview of the assembly of this silicon tracker and discusses in detail studies performed to track quality assurance: leakage current, mechanical alignment and production yields.
  • This paper describes the results of a beam test using the Engineering Model of the GLAST Large Area Telescope, which was installed in a beam of positrons, hadrons and tagged photons at SLAC. The performance of the four subsystems, Anti Coincidence Detector, Silicon Tracker, Calorimeter and Data Acquisition will be described.
  • In September 2007 the Gamma Ray Large Area Space Telescope (GLAST) is scheduled to launch aboard a Delta II rocket in order to put two high-energy gamma-ray detectors, the Large Area Telescope (LAT) and the GLAST Burst Monitor (GBM) into low earth orbit. The Instrument Science Operations Center (ISOC) at SLAC is responsible for the LAT operations for the duration of the mission, and will therefore build an operations center including a monitoring station at SLAC to inform operations staff and visitors of the status of the LAT instrument and GLAST. This monitoring station is to include sky maps showingmore » the location of GLAST in its orbit as well as the LAT's projected field of view on the sky containing known gamma-ray sources. The display also requires a world map showing the locations of GLAST and three Tracking and Data Relay Satellites (TDRS) relative to the ground, their trail lines, and ''footprint'' circles indicating the range of communications for each satellite. The final display will also include a space view showing the orbiting and pointing information of GLAST and the TDRS satellites. In order to build the displays the astronomy programs Xephem, DS9, SatTrack, and STK were employed to model the position of GLAST and pointing information of the LAT instrument, and the programming utilities Python and Cron were used in Unix to obtain updated information from database and load them into the programs at regular intervals. Through these methods the indicated displays were created and combined to produce a monitoring display for the LAT and GLAST.« less