Proceedings of Spie

PROCEEDINGS OF SPIE SPIEDigitalLibrary.org/conference-proceedings-of-spie Arcus: an ISS-attached high- resolution x-ray grating spectrometer R. K. Smith, M. Ackermann, R. Allured, M. W. Bautz, J. Bregman, et al. R. K. Smith, M. Ackermann, R. Allured, M. W. Bautz, J. Bregman, J. Bookbinder, D. Burrows, L. Brenneman, N. Brickhouse, P. Cheimets, A. Carrier, M. Freeman, J. Kaastra, R. McEntaffer, J. Miller, A. Ptak, R. Petre, G. Vacanti, "Arcus: an ISS-attached high-resolution x-ray grating spectrometer," Proc. SPIE 9144, Space Telescopes and Instrumentation 2014: Ultraviolet to Gamma Ray, 91444Y (24 July 2014); doi: 10.1117/12.2062671 Event: SPIE Astronomical Telescopes + Instrumentation, 2014, Montréal, Quebec, Canada Downloaded From: https://www.spiedigitallibrary.org/conference-proceedings-of-spie on 9/14/2018 Terms of Use: https://www.spiedigitallibrary.org/terms-of-use Arcus: an ISS-attached high-resolution X-ray grating spectrometer R. K. Smith1, M. Ackermann2, R. Allured1, M. W. Bautz3, J. Bregman4, J. Bookbinder1, D. Burrows5, L. Brenneman1, N. Brickhouse1, Peter Cheimets1, A. Carrier6, M. Freeman1, J. Kaastra7, R. McEntaffer8, J. Miller4, A. Ptak9, R. Petre9, G. Vacanti2, and the Arcus team 1Smithsonian Astrophysical Observatory, 2cosine Research, 3Massachusetts Institute of Technology, 4University of Michigan, 5Pennsylvania State University, 6Lockheed-Martin Advanced Technology Center, 7SRON, 8University of Iowa, 9NASA Goddard Space Flight Center ABSTRACT We present the design and scientific motivation for Arcus, an X-ray grating spectrometer mission to be deployed on the International Space Station. This mission will observe structure formation at and beyond the edges of clusters and galaxies, feedback from supermassive black holes, the structure of the interstellar medium and the formation and evolution of stars. The mission requirements will be R>2500 and >600 cm2 of effective area at the crucial O VII and O VIII lines, values similar to the goals of the IXO X-ray Grating Spectrometer. The full bandpass will range from 8-52Å (0.25-1.5 keV), with an overall minimum resolution of 1300 and effective area >150 cm2. We will use the silicon pore optics developed at cosine Research and proposed for ESA’s Athena mission, paired with off-plane gratings being developed at the University of Iowa and combined with MIT/Lincoln Labs CCDs. This mission achieves key science goals of the New Worlds, New Horizons Decadal survey while making effective use of the International Space Station (ISS). Keywords: gratings, ISS, instrumentation, X-rays: spectroscopy 1. INTRODUCTION The highly energetic processes involved in the formation Ne IX O VIII O VII N VII N VI C VI C V of galaxies and clusters, the outflows from supermassive FoM = [Resolving Power x Eective Area] (cm) Arcus black holes, and stellar corona magnetospheres all leave signatures in the form of highly ionized metals with charac- 1000 3mÅ teristic temperature, density, and velocity distributions. The Athena (2028) 5mÅ (Athena systematics limit) X-ray gratings on Chandra (HETG, LETG) and the XMM- XMM-Newton RGS Newton (RGS) satellites have sampled, with long observa- tions of the brightest objects, some of the science enabled by 100 Chandra Gratings high-resolution soft X-ray spectroscopy1,2,3,4,5. The current generation of X-ray gratings, however, have only modest Astro-H SXS resolutions (R~200-1200) and efficiencies of only a few per- 5σ detection, 500 ksec obs Line Detection Figure of Merit Line Detection Figure Using 25 blazar LOS with Fx~10 cgs cent, limiting most studies to only a few sources. To make 10 substantial progress in this area, a major leap in capabilities, 10 20 30 40 50 both resolution and effective area, will be required. For- Wavelength (Å) tunately, recent advances in grating technology and X-ray Figure 1 – Arcus figure of merit for detecting weak lines com- optics have enabled such a leap at a modest cost, as shown in pared to existing and future missions. Figures 1, 2, and 3. Arcus (Latin for ‘arc’ or ‘rainbow’) is a proposed SMEX ($125M cap) mission to be installed on the ISS. It will use the off-plane gratings6 that have been under development for Constellation-X and IXO7, combined with the silicon pore optics8 planned for use on ESA’s upcoming Athena mission. The focal plane will use the current generation of CCDs based on the Suzaku9 design, with electronics similar to that of Swift10 and the upcoming TESS11 mission; the pointing system and mission operations will be similar to those planned for NICER12. We describe below the science, instrumentation, and operations plan for Arcus. 2. THE SCIENCE OF ARCUS The soft X-ray bandpass from 8-52Å contains strong transitions from abundant atoms and ions over a broad range of temperatures and ionization parameters, enabling studies of a wide variety of science topics. During the prime mission, we will focus on three specific areas: structure formation, supermassive black hole (SMBH) feedback, and stellar formation and evolution. We briefly describe our specific science plans for each area here. Space Telescopes and Instrumentation 2014: Ultraviolet to Gamma Ray, edited by Tadayuki Takahashi, Jan-Willem A. den Herder, Mark Bautz, Proc. of SPIE Vol. 9144, 91444Y · © 2014 SPIE CCC code: 0277-786X/14/$18 · doi: 10.1117/12.2062671 Proc. of SPIE Vol. 9144 91444Y-1 Downloaded From: https://www.spiedigitallibrary.org/conference-proceedings-of-spie on 9/14/2018 Terms of Use: https://www.spiedigitallibrary.org/terms-of-use Table 1: Arcus Science Traceability Matrix Science Topic Measurement Requirement Goals Structure Trace metals Survey absorption lines of 50 galaxies and clusters 600 cm2 at O VII, 150 cm2 minimum effec- Formation beyond virial to 3x virial radius. Survey 50 LoS through Galactic tivearea throughout, with 8 Msec of observ- radius to test Halo & Local Group to find structure, abundance. ing time. R>1500 over 12-40Å bandpass to formation Measure abundances, velocities, & composition get C, N, O, and Ne ions. R>2500 at O VII theories. within Milky Way. SMBH Measure mass Observe absorption and emission lines from range Bandpass 8-52Å with >150 cm2 EA Feedback & energy in of ions to measure velocities & profiles and tempo- throughout, R>1500 and an observing time outflowing ral variation in response to changing SMBH flux. of 8Msec. SMBH wind. 2 Stellar Life Determine how Map Te and ne, absorption column of pre-shock gas, Bandpass 8-52Å with >250 cm EA Cycle young stars and vturb vs shock cooling. throughout, R>1500 and an observing time dispersed their of 4Msec. disks. 2.1 Structure Formation The natural outcome of the formation of structure is the production of hot gas (105–108K) on the scales of galaxies, galaxy groups and clusters, as well as the collapsing intergalactic filaments that comprise the cosmic web (the ‘Warm- Hot Intergalactic Medium’ or WHIM). The importance of this gas is not simply that it accounts for about half of the baryons in the Universe, but its properties encode the processes that lead to structure formation and evolution. The study of the WHIM is sometimes trivialized as the search for the missing baryons. As mass is conserved, the baryons cannot be missing, but it is the distribution of the baryons with temperature that is crucial in revealing the physical processes relevant to the formation of large-scale structure as well as galaxy formation. For example, the formation of galaxies produces a large number of massive stars and supernovae, along with a central SMBH. These heat the accreting gas in different ways, and although galaxy formation models predict hot extended gaseous halos, there is enormous model variation in the predicted gas mass, temperature and abundance distributions. These vital properties are largely uncon- strained due to the lack of relevant data. Arcus will provide the critical data that will identify the correct astrophysical models for galaxy and larger scale structure formation. In cosmological simulations, the collapse of dark matter filaments is collisionless, but the gaseous component undergoes shocks, heating the gas to WHIM temperatures. The intersections of cosmic filaments are nascent galaxy clusters that grow through the continued inflow from the matter in the connective filaments.The galaxy clusters become virialized (overdensity above 200), but they are difficult to study in emission at radii greater than about half the virial radius. At larger radii, the filaments are non-virialized structures, and where they feed the clusters, their overdensities are predicted to be typically 30-200. This formation of structure model for galaxy clusters has yet to be tested, as information on hot gas near and beyond the virial radius has been extremely challenging to obtain. However, the WHIM absorption studies proposed here can trace both the outer parts of clusters as well as the baryonic filaments that drain into the galaxy clusters. 1200 4 Ir-coated SPO petals The evolution of cold dark matter is probably simple as it is just w/ O-plane Gratings 96% open Silicon mesh lter base the gravitational response to a perturbation spectrum that is measured 1000 ~1000 cm Arcus ) 45 nm polyimide coating 2 from 9-16Å from the CMB. The complications arise in the baryonic component, 70 nm Al optical blocking lter ~900 cm Suzaku-type BI CCD QE which undergoes heating and cooling, and can undergo a variety of 800 at O VII fluid phenomena, including shocks and turbulence. In addition to the 600 ~575 cm shock heating associated with accretion, further heating occurs from at C VI 400 supernovae of massive stars and from AGNs. The amount of ad- Astro-H SXS ditional entropy provided by stars and AGNs is not easily calculated, Effective Area (cm 200 so for simulations that study cluster evolution, a “preheating event” is XMM-Newton RGS Chandra Gratings usually assumed to occur at a redshift when the cluster was just about 0 to form13 (i.e., z ~ 3).

Load more