THE DUST-SCATTERING X-RAY RINGS OF THE ANOMALOUS X-RAY PULSAR 1E 1547.0-5408

Journal Article · Wed Feb 10 04:00:00 EST 2010 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/710/1/227· OSTI ID:21394530

Tiengo, A; Vianello, G; Esposito, P; Mereghetti, S; Giuliani, A ^[1]; Costantini, E ^[2]; Israel, G L; Stella, L; Bernardini, F ^[3]; Turolla, R ^[4]; Zane, S ^[5]; Rea, N ^[6]; Goetz, D ^[7]; Moretti, A ^[8]; Romano, P ^[9]; Ehle, M ^[10]; Gehrels, N ^[11]

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1. INAF/Istituto di Astrofisica Spaziale e Fisica Cosmica-Milano, via E. Bassini 15, 20133 Milano (Italy)
2. SRON, Netherlands Institute for Space Research, Sorbonnelaan 2, 3584 CA Utrecht (Netherlands)
3. INAF/Osservatorio Astronomico di Roma, via Frascati 33, 00040 Monteporzio Catone (Italy)
4. Universita degli Studi di Padova, Dipartimento di Fisica, via F. Marzolo 8, 35131 Padova (Italy)
5. University College London, Mullard Space Science Laboratory, Holmbury St. Mary, Dorking, Surrey RH5 6NT (United Kingdom)
6. Institut de Ciencies de l'Espai (CSIC-IEEC), Campus UAB, Facultat de Ciencies, Torre C5-parell, 08193 Barcelona (Spain)
7. CEA Saclay, DSM/Irfu/Service d'Astrophysique, Orme des Merisiers, Bat. 709, 91191 Gif-sur-Yvette (France)
8. INAF/Osservatorio Astronomico di Brera, via E. Bianchi 46, 23807 Merate (Italy)
9. INAF/Istituto di Astrofisica Spaziale e Fisica Cosmica-Palermo, via U. La Malfa 153, 90146 Palermo (Italy)
10. XMM-Newton Science Operations Centre, ESAC, ESA, P.O. Box 78, 28691 Villanueva de la Canada (Spain)
11. NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)

On 2009 January 22 numerous strong bursts were detected from the anomalous X-ray pulsar 1E 1547.0-5408. Swift/XRT and XMM-Newton/EPIC observations carried out in the following two weeks led to the discovery of three X-ray rings centered on this source. The ring radii increased with time following the expansion law expected for a short impulse of X-rays scattered by three dust clouds. Assuming different models for the dust composition and grain size distribution, we fit the intensity decay of each ring as a function of time at different energies, obtaining tight constraints on the distance of the X-ray source. Although the distance strongly depends on the adopted dust model, we find that some models are incompatible with our X-ray data, restricting to 4-8 kpc the range of possible distances for 1E 1547.0-5408. The best-fitting dust model provides a source distance of 3.91 +- 0.07 kpc, which is compatible with the proposed association with the supernova remnant G327.24-0.13, and implies distances of 2.2 kpc, 2.6 kpc and 3.4 kpc for the dust clouds, in good agreement with the dust distribution inferred by CO line observations toward 1E 1547.0-5408. However, dust distances in agreement with CO data are also obtained for a set of similarly well-fitting models that imply a source distance of {approx}5 kpc. A distance of {approx}4-5 kpc is also favored by the fact that these dust models are already known to provide good fits to the dust-scattering halos of bright X-ray binaries. Assuming N{sub H} = 10{sup 22} cm{sup -2} in the dust cloud responsible for the brightest ring and a bremsstrahlung spectrum with kT = 100 keV, we estimate that the burst producing the X-ray ring released an energy of 10{sup 44}-10{sup 45} erg in the 1-100 keV band, suggesting that this burst was the brightest flare without any long-lasting pulsating tail ever detected from a magnetar.

• OSTI ID: 21394530
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 1 Vol. 710; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
BARYONS
BREMSSTRAHLUNG
CARBON COMPOUNDS
CARBON MONOXIDE
CARBON OXIDES
CHALCOGENIDES
COSMIC RADIO SOURCES
DUSTS
ELECTROMAGNETIC RADIATION
ELEMENTARY PARTICLES
ENERGY RANGE
FERMIONS
GRAIN SIZE
HADRONS
IONIZING RADIATIONS
KEV RANGE
KEV RANGE 10-100
MICROSTRUCTURE
NEUTRONS
NUCLEONS
OXIDES
OXYGEN COMPOUNDS
PULSARS
PULSES
RADIATION SOURCES
RADIATIONS
SCATTERING
SIZE
SPECTRA
STARS
SUPERNOVA REMNANTS
TIME DEPENDENCE
X RADIATION
X-RAY SOURCES