Gamma-ray Large Area Space Telescope. Arecibo Synergy with GLAST (and other gamma-ray telescopes) Frontiers of Astronomy with the World’s Largest Radio Telescope 12 September 2007 Dave Thompson GLAST Large Area Telescope Multiwavelength Coordinator [email protected]
Gamma-ray Large Area Space Telescope
Arecibo Synergy with GLAST (and other gamma-ray telescopes)
Frontiers of Astronomy with the World’s Largest Radio Telescope
12 September 2007
GLAST Large Area Telescope Multiwavelength Coordinator
for the GLAST Mission Team
see http://glast.gsfc.nasa.gov and links therein
GLAST LAT AGILE
Gamma-ray sources are nonthermal, typically produced by interactions of high-energy particles.
Known classes of gamma-ray sources are multiwavelength objects, seen across much of the spectrum.
INTEGRAL GLAST GBM Swift
Gamma-ray Facilities: More Numerous, More Capable
GLAST: Gamma-ray Large Area Space Telescope
Two GLAST instruments:
Large Area Telescope
LAT: 20 MeV – >300 GeV (LAT was originally called GLAST by itself)
LAT field of view ~2.5 sr
GLAST Burst Monitor
GBM: 10 keV – 25 MeV
GBM field of view ~9 sr
Launch: This Winter
Lifetime: 5 years minimum, 10 years goal
What Do Gamma-ray Measurements Offer?
Some Other Needs for Astrophysics
So far, gamma-ray telescopes have only seen the brightest objects – the “tip of the iceberg.” The fainter sources are where Arecibo will be critical.
How do the GALFACTS and GALPROP/gamma-ray studies compare in interpreting the Galactic magnetic field/particle distributions?
What do these results imply about particle confinement and propagation?
Can we use this information to search for local sources of cosmic rays?
What do the combined radio/gamma-ray observations tell us about particle acceleration and interaction – processes, location?
What can this information reveal about jet formation and collimation?
Left: TeV and radio images of M87, one of a handful of radio galaxies seen in gamma rays.
Right: TeV variability of M87.
Is the gamma-ray variability related to changes in the jet? In the core?
What about fainter radio galaxies?
Microquasars – Binary Systems
LSI 5039 – compact object in orbit around an O star.
Gamma-ray emission varies during the 4 day orbit.
VLBI suggests that the emission comes from a jet.
LSI +61 303 – compact object in orbit around a Be star.
Gamma-ray emission varies during the 26 day orbit.
VLBI suggests that the emission comes from a pulsar wind.
What sort of compact object?
How are the particles accelerated?
Are there different types of such high-mass binary systems?
Over half the sources in the third EGRET catalog remain unidentified.
GLAST will detect many more sources.
Identifying and understanding such sources will be a multiwavelength challenge.
What other types of objects produce high-energy gamma rays and radio?
Are there radio-quiet gamma-ray sources (e.g. beamed)?
The nonthermal nature of high-energy gamma-ray emission almost assures that gamma-ray sources will be radio sources.
The new generation of gamma-ray telescopes is already expanding the number and types of sources, and this process will accelerate with GLAST.
Radio, especially the great sensitivity of Arecibo, will be a critical partner with gamma-ray astrophysics.