Timing and flux evolution of the galactic center magnetar SGR J1745–2900

Journal Article · Sat May 10 00:00:00 EDT 2014 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/786/2/84· OSTI ID:22356964

Kaspi, Victoria M.; Archibald, Robert F.; Dufour, François; An, Hongjun ^[1]; Bhalerao, Varun ^[2]; Gotthelf, Eric V.; Beloborodov, Andrei M.; Hailey, Charles J.; Mori, Kaya ^[3]; Bachetti, Matteo ^[4]; Boggs, Steven E.; Craig, William W. ^[5]; Christensen, Finn E. ^[6]; Grefenstette, Brian W.; Harrison, Fiona A.; Madsen, Kristin K. ^[7]; Kennea, Jamie A. ^[8]; Kouveliotou, Chryssa ^[9]; Markwardt, Craig B. ^[10]; Stern, Daniel ^[11] ; others, and

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1. Department of Physics, McGill University, Montreal, Quebec, H3A 2T8 (Canada)
2. Inter-University Center for Astronomy and Astrophysics, Post Bag 4, Ganeshkhind, Pune 411007 (India)
3. Columbia Astrophysics Laboratory, Columbia University, New York, NY 10027 (United States)
4. Université de Toulouse, UPS-OMP, IRAP, Toulouse (France)
5. Space Sciences Laboratory, University of California, Berkeley, CA 94720 (United States)
6. DTU Space, National Space Institute, Technical University of Denmark, Elektrovej 327, DK-2800 Lyngby (Denmark)
7. Cahill Center for Astronomy and Astrophysics, California Institute of Technology, Pasadena, CA 91125 (United States)
8. Department of Astronomy and Astrophysics, The Pennsylvania State University, 525 Davey Lab, University Park, PA 16802 (United States)
9. Astrophysics Office, ZP 12, NASA Marshall Space Flight Center, Huntsville, AL 35812 (United States)
10. Goddard Space Flight Center, Greenbelt, MD 20771 (United States)
11. Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States)

We present the X-ray timing and spectral evolution of the Galactic Center magnetar SGR J1745–2900 for the first ∼4 months post-discovery using data obtained with the Nuclear Spectroscopic Telescope Array and Swift observatories. Our timing analysis reveals a large increase in the magnetar spin-down rate by a factor of 2.60 ± 0.07 over our data span. We further show that the change in spin evolution was likely coincident with a bright X-ray burst observed in 2013 June by Swift, and if so, there was no accompanying discontinuity in the frequency. We find that the source 3-10 keV flux has declined monotonically by a factor of ∼2 over an 80 day period post-outburst accompanied by a ∼20% decrease in the source's blackbody temperature, although there is evidence for both flux and kT having leveled off. We argue that the torque variations are likely to be magnetospheric in nature and will dominate over any dynamical signatures of orbital motion around Sgr A*.

• OSTI ID: 22356964
• Journal Information: Astrophysical Journal, Vol. 786, 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
EVOLUTION
GALAXIES
KEV RANGE
MAGNETIC FIELDS
NEUTRON STARS
PULSARS
SPIN
STARS
TELESCOPES
TORQUE
VARIATIONS
X RADIATION