ﻻ يوجد ملخص باللغة العربية
We present commissioning data for the POLISH instrument obtained on the Hale 5-m telescope. The goal of this high precision polarimeter is to constrain orbital inclination of high mass X-ray binaries and to therefore obtain independent mass estimates for their black hole companions. We have obtained photon shot noise limited precision on standard stars, and we have measured the polarization of bright stars at the part per million level on a nightly basis. Systematic effects have been reduced to less than 1% of the measured polarization for polarized sources and to the part per million level for weakly polarized sources. The high sensitivity of this instrument to asymmetry suggests that valuable contributions will be made in many other fields, including studies of extrasolar planets, debris disks, and stellar astrophysics.
We have built a polarimeter in order to measure the electron beam polarization in hall C at JLAB. Using a superconducting solenoid to drive the pure-iron target foil into saturation, and a symmetrical setup to detect the Moller electrons in coinciden
High Mass X-ray Binaries (HMXBs) are interesting objects that provide a wide range of observational probes to the nature of the two stellar components, accretion process, stellar wind and orbital parameters of the systems. A large fraction of the tra
Strongly magnetized, accreting neutron stars show periodic and aperiodic variability over a wide range of time scales. By obtaining spectral and timing information on these different time scales, we can have a closer look into the physics of accretio
We present the results of our monitoring program to study the long-term variability of the Halpha line in high-mass X-ray binaries. We have carried out the most complete optical spectroscopic study of the global properties of high-mass X-ray binaries
Many high-mass X-ray binaries (HMXBs) are runaways. Stellar wind and radiation of donor stars in HMXBs along with outflows and jets from accretors interact with the local interstellar medium and produce curious circumstellar structures. Several such