相关论文: Optical Observations of SAX J1808.4-3658 During Qu…

The optical counterpart of the binary millisecond X-ray pulsar SAX J1808.4-3658 during quiescence was detected at V = 21.5 mag by Homer et al. (2001). This star shows a 6% semi-amplitude sinusoidal modulation of its flux at the orbital…

We report on time-resolved optical imaging of the X-ray binary SAX J1808.4-3658 during its quiescent state and 2008 outburst. The binary, containing an accretion-powered millisecond pulsar, has a large sinusoidal-like modulation in its…

We report on optical imaging of the X-ray binary SAX J1808.4-3658 with the 8-m Gemini South Telescope. The binary, containing an accretion-powered millisecond pulsar, appears to have a large periodic modulation in its quiescent optical…

We report the first extensive set of optical photometric observations of the counterpart to SAX J1808.4-3658 (V4580 Sagittarius) in quiescence. The source was detected at V~21, 5 magnitudes fainter than at the peak of its 1998 outburst.…

Observations of the accretion powered millisecond pulsar SAX J1808.4-3658 have revealed an interesting binary evolution, with the orbit of the system expanding at an accelerated rate. We use the recent finding that the accreted fuel in SAX…

Millisecond radio pulsars are neutron stars that have been spun-up by the transfer of angular momentum during the low-mass X-ray binary phase. The transition from an accretion-powered to a rotation-powered pulsar takes place on evolutionary…

The accreting millisecond pulsar SAX J1808.4-3658 may be a transition object between accreting X-ray binaries and millisecond radio pulsars. We have constrained the thermal radiation from its surface through XMM-Newton X-ray observations,…

The evolutionary status of the low mass X-ray binary SAX J1808.4-3658 is simulated by following the binary evolution of its possible progenitor system through mass transfer, starting at a period of $\sim$6.6 hr. The evolution includes…

SAX J1808.4-3658 is a unique source being the first Low Mass X-ray Binary showing coherent pulsations at a spin period comparable to that of millisecond radio pulsars. Here we present an XMM-Newton observation of SAX J1808.4-3658 in…

We observed SAX J1808.4-3658 (1808), the first accreting millisecond pulsar, in deep quiescence with XMM-Newton and (near-simultaneously) Gemini-South. The X-ray spectrum of 1808 is similar to that observed in quiescence in 2001 and 2006,…

The accreting millisecond X-ray pulsar (AMXP) SAX J1808.4-3658, shows a peculiar orbital evolution that proceeds at a much faster pace than predicted by conservative binary evolution models. It is important to identify the underlying…

Recent timing analysis reveals that the orbital period of the first discovered accreting millisecond pulsar SAX J1808.4-3658 is increasing at a rate $\dot{P}_{\rm orb}=(3.89\pm0.15)\times 10^{-12}~\rm s\,s^{-1}$, which is at least one order…

We present a timing analysis of the 2015 outburst of the accreting millisecond X-ray pulsar SAX J1808.4-3658, using non-simultaneous XMM-Newton and NuStar observations. We estimate the pulsar spin frequency and update the system orbital…

We report on a 20 ks BeppoSAX observation of the transient 2.5 ms X-ray pulsar SAX J1808.4-3658 in its quiescent state. A source at a level of ~ 3 x 10^-3 c/s was detected with the BeppoSAX/MECS at a position consistent with that of SAX…

A set of CCD images have been obtained during the decline of the X-ray transient SAX J1808.4-3658 during April-June 1998. The optical counterpart has been confirmed by several pieces of evidence. The optical flux shows a modulation on…

The pulse profiles of the accreting X-ray millisecond pulsar SAX J1808.4-3658 at different energies are studied. The two main emission component, a black body and a power-law tail, clearly identified in the time-averaged spectrum, do not…

We present a 7 yr timing study of the 2.5 ms X-ray pulsar SAX J1808.4-3658, an X-ray transient with a recurrence time of ~2 yr, using data from the Rossi X-ray Timing Explorer covering 4 transient outbursts (1998-2005). We verify that the…

We present multiband optical/infrared photometry of V4580 Sgr, the optical counterpart of the accretion-powered millisecond pulsar SAX J1808.4-3658, taken during the 1998 X-ray outburst of the system. The optical flux is consistent with…

The Rossi X-ray Timing Explorer has observed five outbursts from the transient 2.5 ms accretion-powered pulsar SAX J1808.4-3658 during 1998-2008. We present a pulse timing study of the most recent outburst and compare it with the previous…

We present an analysis of X-ray, Ultraviolet and optical/near-IR photometric data of the transitional millisecond pulsar binary XSSJ12270-4859, obtained at different epochs after the transition to a rotation-powered radio pulsar state. The…