منابع مشابه
X-ray Timing, Spectroscopy and Photometry of the Anomalous X-ray Pulsar
We present new X-ray timing and spectral results on the 8.0-second X-ray pulsar CXOU J010043.1– 721134 from a series of observations using the Chandra X-ray Observatory. We find a spin period in 2004 January of 8.020392±0.000009 seconds. Comparison of this to 2001 Chandra observations implies a period derivative Ṗ = (1.88 ± 0.08) × 10 s s, leading to an inferred dipole surface magnetic field fo...
متن کاملHardness Ratio Estimation in Low Counting X-ray Photometry
Hardness ratios are commonly used in X-ray photometry to indicate spectral properties roughly. It is usually defined as the ratio of counts in two different wavebands. This definition, however, is problematic when the counts are very limited. Here we instead define hardness ratio using the λ parameter of Poisson processes, and develop an estimation method via Bayesian statistics. Our Monte Carl...
متن کاملSimultaneous optical and X-ray high speed photometry of Cyg X-2
The X-ray emission from X-ray binaries may originate in flares occurring when magnetic loops anchored in the disc reconnect. In analogy with our Sun, Hα emission should arise as the accelerated electrons thermalize in the optically emitting disc, perhaps leading to correlated variability between X-rays, Hα and the optical continuum. We present simultaneous X-ray and optical high speed photometr...
متن کاملForty Years of X-Ray Binaries
In 2012 it was forty years ago that the discovery of the first X-ray binary Centaurus X-3 became known. That same year it was discovered that apart from the High-Mass X-ray Binaries (HMXBs) there are also Low-Mass X-ray Binaries (LMXBs), and that Cygnus X-1 is most probably a black hole. By 1975 also the new class of Be/X-ray binaries was discovered. After this it took 28 years before ESAs INTE...
متن کاملIdentification of the optical counterparts of high-mass X-ray binaries through optical photometry and spectroscopy
We present the results of our search for optical counterparts to high-mass X-ray transient sources discovered by various X-ray missions. We obtained CCD images of the X-ray fields through BVR and Hα filters in order to identify early-type stars in the R − Hα versus B − V colour-colour diagram. We also obtained medium-resolution spectroscopy of the candidates in order to confirm the presence of ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Monthly Notices of the Royal Astronomical Society: Letters
سال: 2015
ISSN: 1745-3925,1745-3933
DOI: 10.1093/mnrasl/slv084