A FOCUSED, HARD X-RAY LOOK AT ARP 299 WITH NuSTAR

Journal Article · Fri Feb 20 00:00:00 EST 2015 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/800/2/104· OSTI ID:22522113

Ptak, A.; Hornschemeier, A.; Lehmer, B.; Yukita, M.; Wik, D.; Tatum, M. ^[1]; Zezas, A. ^[2]; Antoniou, V. ^[3]; Argo, M. K. ^[4]; Ballo, L.; Della Ceca, R. ^[5]; Bechtol, K. ^[6]; Boggs, S.; Craig, W. W.; Krivonos, R. ^[7]; Christensen, F. E. ^[8]; Hailey, C. J. ^[9]; Harrison, F. A. ^[10]; Maccarone, T. J. ^[11]; Stern, D. ^[12] ; others, and

---

1. NASA Goddard Space Flight Center, Code 662, Greenbelt, MD 20771 (United States)
2. Department of Physics, University of Crete, Herakleion (Greece)
3. Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)
4. Jodrell Bank Centre for Astrophysics, The University of Manchester, Oxford Road, Manchester M13 9PL (United Kingdom)
5. Osservatorio Astronomico di Brera (INAF), via Brera 28, I-20121 Milano (Italy)
6. Kavli Institute for Cosmological Physics, Chicago, IL 60637 (United States)
7. U.C. Berkeley Space Sciences Laboratory, Berkeley, CA (United States)
8. National Space Institute, Technical University of Denmark, DK-2100 Copenhagen (Denmark)
9. Columbia University, New York, NY (United States)
10. Caltech Division of Physics, Mathematics and Astronomy, Pasadena, CA (United States)
11. Department of Physics, Texas Tech University, Lubbock, TX 79409 (United States)
12. Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States)

We report on simultaneous observations of the local starburst system Arp 299 with NuSTAR and Chandra, which provides the first resolved images of this galaxy up to energies of ∼45 keV. Fitting the 3-40 keV spectrum reveals a column density of N {sub H} ∼ 4 × 10{sup 24} cm{sup –2}, characteristic of a Compton-thick active galactic nucleus (AGN), and a 10-30 keV luminosity of 1.2 × 10{sup 43} erg s{sup –1}. The hard X-rays detected by NuSTAR above 10 keV are centered on the western nucleus, Arp 299-B, which previous X-ray observations have shown to be the primary source of neutral Fe-K emission. Other X-ray sources, including Arp 299-A, the eastern nucleus also thought to harbor an AGN, as well as X-ray binaries, contribute ≲ 10% to the 10-20 keV emission from the Arp 299 system. The lack of significant emission above 10 keV other than that attributed to Arp 299-B suggests that: (1) any AGN in Arp 299-A must be heavily obscured (N {sub H} > 10{sup 24} cm{sup –2}) or have a much lower luminosity than Arp 299-B and (2) the extranuclear X-ray binaries have spectra that cut-off above ∼10 keV. Such soft spectra are characteristic of ultraluminous X-ray sources observed to date by NuSTAR.

• OSTI ID: 22522113
• Journal Information: Astrophysical Journal, Vol. 800, Issue 2; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
BINARY STARS
COSMIC X-RAY SOURCES
DENSITY
GALAXY NUCLEI
HARD X RADIATION
IMAGES
KEV RANGE
LUMINOSITY
X-RAY GALAXIES