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Seventeen accreting neutron star pulsars, mostly high mass X-ray binaries with half of them Be-type transients, are known to exhibit Cyclotron Resonance Scattering Features (CRSFs) in their X-ray spectra, with characteristic line energies from 10 to 60 keV. To date about two thirds of them, plus a few similar systems without known CRSFs, have been observed with Suzaku. We present an overview of results from these observations, including the discovery of a CRSF in the transient 1A 1118-61 and pulse phase resolved spectroscopy of GX 301-2. These observations allow for the determination of cyclotron line parameters to an unprecedented degree of accuracy within a moderate amount of observing time. This is important since these parameters vary-e.g., with orbital phase, pulse phase, or luminosity-depending on the geometry of the magnetic field of the pulsar and the properties of the accretion column at the magnetic poles. We briefly introduce a spectral model for CRSFs that is currently being developed and that for the first time is based on these physical properties. In addition to cyclotron line measurements, selected highlights from the Suzaku analyses include dip and flare studies, e.g., of 4U 1907+09 and Vela X-1, which show clumpy wind effects (like partial absorption and/or a decrease in the mass accretion rate supplied by the wind) and may also display magnetospheric gating effects. [ABSTRACT FROM AUTHOR]

We compiled X-ray and Optical observations of the accreting X-ray binary sytem A0535+26 since its discovery in 1975, that will allow us to shed light on the unpredictible behavior of this binary system. We present the data in terms of the Be-disc interaction with the neutron star companion. In addition, we show recent results from the continous monitoring of this source by the Gamma-ray Burst Monitor (GBM), on board the Fermi observatory, since its launch in 2008 June 11. [ABSTRACT FROM AUTHOR]

We compiled X-ray and Optical observations of the accreting X-ray binary sytem A 0535+26 since its discovery in 1975, that will allow us to shed light on the unpredictible behavior of this binary system. We present the data in terms of the Be-disc interaction with the neutron star companion. In addition, we show recent results from the continous monitoring of this source by the Gamma-ray Burst Monitor (GBM), on board the Fermi observatory, since its launch in 2008 June 11. [ABSTRACT FROM AUTHOR]

The Be/X-ray binary A0535+26 has shown three giant outbursts since 2005, after a long period of quiescence. The giant outbursts in 2005 (~5.2 Crab, 15-50 keV range) and 2009 (~5.6 Crab) could not be observed by most X-ray observatories due to Sun observing constraints. Finally, a giant outburst in February 2011, that reached a flux of ~3.8 Crab, was monitored with INTEGRAL and Swift TOO observations. We present first results of these observations, with a special focus on the cyclotron lines present in the X-ray spectrum of the source. [ABSTRACT FROM AUTHOR]

OAO 1657-415 is an eclipsing X-ray binary pulsar that has undergone several torque reversals throughout its long history of observation. We present a frequency history spanning nearly 19 years of observations from the Burst and Transient Source Experiment (BATSE) and from the Gamma-Ray Burst Monitor (GBM). Orbital ephemerides of the pulsar system is obtained at several intervals throughout this history. With these ephemerides, statistically significant orbital decay is established. [ABSTRACT FROM AUTHOR]

A new outburst of the Be/X-ray binary system A0535+26 took place in August 2009. It is the fourth in a series of normal outbursts that have occurred around the periastron passage of the source, but is unusual by starting at an earlier orbital phase and by presenting a peculiar double-peaked light curve. TOO observations have been performed with INTEGRAL, RXTE and Suzaku. First results of these observations are presented, with special emphasis on the cyclotron lines present in the X-ray spectrum of the source, as well as in the pulse period and energy dependent pulse profiles of the source. [ABSTRACT FROM AUTHOR]