NuSTAR is a NASA Small Explorer Mission that will be the first focusing hard X-ray (5-80 keV) telescope. It has three primary science goals: 1) discover collapsed stars and black holes on all scales, 2) characterize compact stellar remnants near the Galactic center, and 3) identify massive black holes in galaxy surveys. NuSTAR will provide unprecedented sensitivity, angular resolution, and spectral resolution in the hard X-ray band to study supernova remnants, black holes, gamma-ray bursts, and other energetic phenomena.

1. NuSTAR
The Nuclear Spectroscopic Telescope Array (NuSTAR)
Hard X-ray (5 - 80 keV) Small Explorer (SMEX) mission
Selected 11/2003 for a Phase A study
Downselection 11/2005
Caltech, JPL, Columbia, LLNL, DSRI, UCSC, SLAC, Spectrum Astro
CIT JPL Columbia LLNL DSRI UCSC SLAC Spectrum

2. NuSTAR
NuSTAR
the first focusing
mission above 10 keV
brings unparalleled
 sensitivity,
 angular resolution, and
 spectral resolution
to the hard x-ray band
and opens an entirely new region of the electromagnetic
spectrum for sensitive study
CIT JPL Columbia LLNL DSRI UCSC SLAC Spectrum

3. NuSTAR
NuSTAR has three primary science goals:
NuSTAR will discover collapsed stars and black holes on all
scales as a pathfinder for the Beyond Einstein missions
Characterize compact stellar
remnants near the Galactic
center
Identify massive black holes in
the NDWFS (wide - 9 deg2) and
GOODS (deep-500’2) survey
fields
CIT JPL Columbia LLNL DSRI UCSC SLAC Spectrum

4. NuSTAR
NuSTAR will map the remnants of recent supernova explosions,
testing theories of where the elements are born
SN 1987A
NuSTAR will measure and map the
44
Ti lines at 68 and 78 keV in historic
remnants:
Tycho, Kepler, Cas A and SN1987A
CIT JPL Columbia LLNL DSRI UCSC SLAC Spectrum

5. NuSTAR
NuSTAR will explore the most extreme physical environments in
the Universe, teaming with GLAST and Chandra to span the high-
energy spectrum
NuSTAR will test our
understanding of all
types of black-hole
powered active
galaxies
Example: GLAST’s measurements of Compton radiation in the blazar Markarian 501 are
compromised without NuSTAR’s simultaneous measurements of the time variable synchrotron
peak (SSC model is shown). Together, they strongly constrain physical models.
CIT JPL Columbia LLNL DSRI UCSC SLAC Spectrum

6. NuSTAR
Other objectives:
Study cosmic ray acceleration in young SNR
Measure high-energy diffuse Galactic emission
Detect hard X-ray emission from galaxy clusters
Map pulsar winds in the Crab
Measure cyclotron lines in Her X-1
Unravel physics of GRBs through followup of Glast events
Test models of Type 1a Sne
CIT JPL Columbia LLNL DSRI UCSC SLAC Spectrum

7. NuSTAR
Core collapse events
SNe lightcurves powered by radioactive decay of elements
produced in non-equilibrium conditions of explosion
Following gamma-ray emission lines after core-collapse
provides critical tests of explosion models - difficult in core-
collapse events
Imaging gamma-ray emisison in a young remnant, before they
enter the Sedov phase also provides a detailed understanding
of the explostion dynamics.
CIT JPL Columbia LLNL DSRI UCSC SLAC Spectrum

8. NuSTAR
• 44Ti - (τ = 85 yr) - produced near the mass cut during α-rich freeze-
out SN 1987A
• Production and ejection very sensitive to explosion mechanism and
ejecta dynamics.
• Believed to now power the 1987A lightcurve
•Gamma-ray lines at 68/78 keV, 1157 keV (detected by Comptel in
Cas A
Flux measurement: 44Ti yield (inferred to be high in
1987a)
Mapping remnants: measure global asymmetries,
ejecta mixing from velocity measurements
CIT JPL Columbia LLNL DSRI UCSC SLAC Spectrum

9. NuSTAR
Line flux sensitivity - ~2 x 10-7 ph/cm2/s
(106 s)
Map 3 young remnants
Measure asymmetry, velocity distribution
Clumpyness
Measure flux from SN1987a
Remnant Age Dist Size 67.9 keV flux
(yr) (kpc) (‘) (x 10-6 ph/cm2/s)
SN 1987a 20 50 0 2.5
Cas A 327 3.4 3.6 15
Kepler 403 2.9 3.5 8.4 (?)
Tycho 435 2.3 8x5 9.2
CIT JPL Columbia LLNL DSRI UCSC SLAC Spectrum

10. NuSTAR
Type 1a Supernovae
SNe 1a widely believed to result from thermonuclear incineration
of an accreting C/O white dwarf. We don’t know:
nature and evolution of the progenitor system
mass of dwarf at ignition
physics of subsequent nuclear burning
reason for the (empirical) width-optical luminosity relation
The lightcurve is believed to be powered by the decay of 56Ni
A SN 1a has never been observed in the X-ray/gamma-ray
Observations of the time evolution of the 56Ni line (158 keV) would
provide important constraints on the explosion mechanism and
dynamics
CIT JPL Columbia LLNL DSRI UCSC SLAC Spectrum

11. Prompt Decay of 56Ni i Type Ia SNe NuSTAR
Evolution of the 56Ni in Type Ia SNe is sensitive to the explosion mechanism and
mixing. For example, Mch and sub-Mch models can be easily distinguished.
NuSTAR can measure evolution of down-scattered HXR photons to Virgo.
CIT JPL Columbia LLNL DSRI UCSC SLAC Spectrum

12. Ready NuSTAR
Although it brings new capabilities to space, NuSTAR is solidly based on
existing hardware developed in a 9 years in a NASA SR&T program
Based on the
Spectrum
Astro SA200-S
bus, the
NuSTAR
spacecraft has
extensive
heritage.
NuSTAR will
be launched
into an
equatorial orbit
from
Kwajalein.
The four NuSTAR The 9m NuSTAR
telescopes have mast is a direct NuSTAR det-
direct heritage to adaptation of the ector modules
the completed 60m mast are the HEFT
HEFT flight optics. successfully flown flight units.
on SRTM.
CIT JPL Columbia LLNL DSRI UCSC SLAC Spectrum