Aims.4U 2129+47 was discovered in the early 80's and classified as an accretion disk corona source due to its broad and partial X-ray eclipses. The 5.24 h binary orbital period was inferred from the X-ray and optical light curve modulation, implying a late K or M spectral type companion star. The source entered a low state in 1983, during which the optical modulation disappeared and an F8 IV star was revealed, suggesting that 4U 2129+47 might be part of a triple system. The nature of 4U 2129+47 has since been investigated, but no definitive conclusion has been reached. Methods.Here, we present timing and spectral analyses of two XMM-Newton  observations of this source, carried out in May and June, 2005. Results.We find evidence for a delay between two mid-eclipse epochs measured ~22 days apart, and we show that this delay can be naturally explained as being due to the orbital motion of the binary 4U 2129+47 around the center of mass of a triple system. This result thus provides further support in favor of the triple nature of 4U 2129+47

BOZZO E, FALANGA M, PAPITTO A, STELLA L, PERNA R, LAZZATI D, et al. (2007). X-Ray Eclipse Time Delays in 4U2129+47. ASTRONOMY & ASTROPHYSICS, 476(1), 301-306 [10.1051/0004-6361:20078444].

X-Ray Eclipse Time Delays in 4U2129+47

DI SALVO, Tiziana;
2007

Abstract

Aims.4U 2129+47 was discovered in the early 80's and classified as an accretion disk corona source due to its broad and partial X-ray eclipses. The 5.24 h binary orbital period was inferred from the X-ray and optical light curve modulation, implying a late K or M spectral type companion star. The source entered a low state in 1983, during which the optical modulation disappeared and an F8 IV star was revealed, suggesting that 4U 2129+47 might be part of a triple system. The nature of 4U 2129+47 has since been investigated, but no definitive conclusion has been reached. Methods.Here, we present timing and spectral analyses of two XMM-Newton  observations of this source, carried out in May and June, 2005. Results.We find evidence for a delay between two mid-eclipse epochs measured ~22 days apart, and we show that this delay can be naturally explained as being due to the orbital motion of the binary 4U 2129+47 around the center of mass of a triple system. This result thus provides further support in favor of the triple nature of 4U 2129+47
BOZZO E, FALANGA M, PAPITTO A, STELLA L, PERNA R, LAZZATI D, et al. (2007). X-Ray Eclipse Time Delays in 4U2129+47. ASTRONOMY & ASTROPHYSICS, 476(1), 301-306 [10.1051/0004-6361:20078444].
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Utilizza questo identificativo per citare o creare un link a questo documento: http://hdl.handle.net/10447/22136
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