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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. NuSTAR the first focusing mission above 10 keV
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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
NuSTARthe 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
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 stellarremnants near the Galactic center Identify massive black holes in the NDWFS (wide - 9 deg2) and GOODS (deep-500’2) survey fields
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 44Ti lines at 68 and 78 keV in historic remnants: Tycho, Kepler, Cas A and SN1987A
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.
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
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.
44Ti - (t = 85 yr) - produced near the mass cut during a-rich freeze-out • 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 SN 1987A Flux measurement:44Ti yield (inferred to be high in 1987a) Mapping remnants: measure global asymmetries, ejecta mixing from velocity measurements
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
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
Prompt Decay of 56Ni i Type Ia SNe 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.
Ready 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 telescopes have direct heritage to the completed HEFT flight optics. The 9m NuSTAR mast is a direct adaptation of the 60m mast successfully flown on SRTM. NuSTAR det-ector modules are the HEFT flight units.