85 research outputs found
Hamas\u27s ascension and its international relations : literature review
This paper focuses on a literature review and summarizes the international relations in which Hamas or its preceding Muslim Brotherhood in Palestine has been situated. Its relations with Israel, the U.S., Russia, Iran, and other Arab countries are overviewed based on previous studies. The diplomatic policy of Hamas is also investigated regarding its own approach and relations with other countries
Hamas and the Gaza war of 2014 : developments since the arab spring in Palestine
This paper demonstrates the impacts of the Arab Spring on Palestine\u27s internal and international politics. It also indicates their links with the subsequent Gaza War in the summer of 2014. A special focus is on Hamas, an offshoot of the Muslim Brotherhood, which was already in power before 2011, though under pressure because of economic sanctions and denial of recognition. Considering such pressure, the associated developments can be explained as a natural consequence
Simultaneous X-ray and Optical Observations of EX Hydrae
The intermediate polar, EX Hydrae, was the object of a large simultaneous
multiwavelength observational campaign during 2000 May - June. Here we present
the Rossi X-ray Timing Explorer photometry and optical photometry and
spectroscopy from ground-based observatories obtained as part of this campaign.
Balmer line radial velocities and Doppler maps provide evidence for an extended
bulge along the outer edge of the accretion disk and some form of
extended/overflowing material originating from the hot spot. In addition, the
optical binary eclipse possesses an extended egress shoulder, an indication
that an additional source (other than the white dwarf) is coming out of
eclipse. We also compare the X-ray and optical results with the results
obtained from the EUV and UV observations from the multiwavelength data set.Comment: to appear in the Astronomical Journal, April 200
Far-ultraviolet Emission-line Morphologies of the Supernova Remnant G65.3+5.7
We present the first far-ultraviolet (FUV) emission-line morphologies of the
whole region of the supernova remnant (SNR) G65.3+5.7 using the FIMS/SPEAR
data. The morphologies of the C IV {\lambda}{\lambda}1548, 1551, He II
{\lambda}1640, and O III] {\lambda}{\lambda}1661, 1666 lines appear to be
closely related to the optical and/or soft X-ray images obtained in previous
studies. Dramatic differences between the C IV morphology and the optical [O
III] {\lambda}5007 image provide clues to a large resonant-scattering region
and a foreground dust cloud. The FUV morphologies also reveal the overall
distribution of various shocks in different evolutionary phases and an
evolutionary asymmetry between the east and the southwest sides in terms of
Galactic coordinates, possibly due to a Galactic density gradient in the global
scale. The relative X-ray luminosity of G65.3+5.7 to C IV luminosity is
considerably lower than those of the Cygnus Loop and the Vela SNRs. This
implies that G65.3+5.7 has almost evolved into the radiative stage in the
global sense and supports the previous proposal that G65.3+5.7 has lost its
bright X-ray shell and become a member of mixed-morphology SNRs as it has
evolved beyond the adiabatic stage.Comment: 6 pages, 3 figures, accepted for publication in The Ap
Observation of the Far-ultraviolet Continuum Background with SPEAR/FIMS
We present the general properties of the far-ultraviolet (FUV; 1370-1720A)
continuum background over most of the sky, obtained with the Spectroscopy of
Plasma Evolution from Astrophysical Radiation instrument (SPEAR, also known as
FIMS), flown aboard the STSAT-1 satellite mission. We find that the diffuse FUV
continuum intensity is well correlated with N_{HI}, 100 m, and H-alpha
intensities but anti-correlated with soft X-ray. The correlation of the diffuse
background with the direct stellar flux is weaker than the correlation with
other parameters. The continuum spectra are relatively flat. However, a weak
softening of the FUV spectra toward some sight lines, mostly at high Galactic
latitudes, is found not only in direct-stellar but also in diffuse background
spectra. The diffuse background is relatively softer that the direct stellar
spectrum. We also find that the diffuse FUV background averaged over the sky
has about the same level as the direct-stellar radiation field in the
statistical sense and a bit softer spectrum compared to direct stellar
radiation. A map of the ratio of 1400-1510A to 1560-1660A shows that the sky is
divided into roughly two parts. However, this map shows a lot of patchy
structures on small scales. The spatial variation of the hardness ratio seems
to be largely determined by the longitudinal distribution of spectral types of
stars in the Galactic plane. A correlation of the hardness ratio with the FUV
intensity at high intensities is found but an anti-correlation at low
intensities. We also find evidence that the FUV intensity distribution is
log-normal in nature.Comment: 39 pages, 26 figures, accepted for publication in ApJ
Far-ultraviolet Observations of the North Ecliptic Pole with SPEAR
We present SPEAR/FIMS far-ultraviolet observations near the North Ecliptic
Pole. This area, at b~30 degrees and with intermediate HI column, seems to be a
fairly typical line of sight that is representative of general processes in the
diffuse ISM. We detect a surprising number of emission lines of many elements
at various ionization states representing gas phases from the warm neutral
medium (WNM) to the hot ionized medium (HIM). We also detect fluorescence bands
of H2, which may be due to the ubiquitous diffuse H2 previously observed in
absorption.Comment: 5 pages, 3 figures, Accepted for publication in ApJ Letter
Molecular Hydrogen Fluorescence in the Eridanus Superbubble
The first FUV (lambda lambda 1350-1750 A) spectral imaging observations of
the Eridanus superbubble, obtained with the SPEAR/FIMS mission, have revealed
distinct fluorescent emission from molecular hydrogen. In this study, the
observed emission features were compared with those from a photo-dissociation
region model with assumed illuminating stellar fields. The result showed rather
high line ratios of I_{1580}/I_{1610}, which may imply the existence of
high-temperature molecular clouds in the region. The H_2 fluorescence intensity
showed a proportional correlation with H-alpha emission, indicating that the
fluorescence and the recombination emission have similar physical origins.Comment: 10 pages, 3 figures, apjl accepte
Experimental and Theoretical Electron Paramagnetic Resonance (EPR) Study on the Temperature-Dependent Structural Changes of Methylsulfanylmethane
Methylsulfonylmethane (or dimethyl sulfone), a naturally produced and vitally important organosulfur compound in living organisms, was irradiated with gamma rays, and the produced radicals were investigated using electron paramagnetic resonance spectroscopy at different temperatures. The structure and behavior of the radical changed when the temperatures varied. The hyperfine splitting of the CH3 group was small, and the 33S splitting was relatively high between 80 and −50 °C. When the temperature was between −50 and −160 °C, the 33S splitting became small and the CH3 splitting was higher. However, the group kept rotating; therefore, only the isotropic splitting values were measured, and the g-values were anisotropic. When the temperature decreased below −180 °C, the CH3 group stopped rotating, and the hydrogen splitting values became nonequivalent due to an inhomogeneous electron distribution. The observed structures can be explained by referring to both the experimental and theoretically calculated values reported
The Spectroscopy of Plasma Evolution from Astrophysical Radiation Mission
The Spectroscopy of Plasma Evolution from Astrophysical Radiation (or the
Far-ultraviolet Imaging Spectrograph) instruments, flown aboard the STSAT-1
satellite mission, have provided the first large-area spectral mapping of the
cosmic far ultraviolet (FUV, lambda 900-1750 Ang) background. We observe
diffuse radiation from hot (10^4 to 10^6 K) and ionized plasmas, molecular
hydrogen, and dust scattered starlight. These data provide for the
unprecedented detection and discovery of spectral emission from a variety of
interstellar environments, including the general medium, molecular clouds,
supernova remnants, and super-bubbles. We describe the mission and its data,
present an overview of the diffuse FUV sky's appearance and spectrum, and
introduce the scientific findings detailed later in this volume
Support for UNRWA's survival
The United Nations Relief and Works Agency for Palestine Refugees in the Near East (UNRWA) provides life-saving humanitarian aid for 5·4 million Palestine refugees now entering their eighth decade of statelessness and conflict. About a third of Palestine refugees still live in 58 recognised camps. UNRWA operates 702 schools and 144 health centres, some of which are affected by the ongoing humanitarian disasters in Syria and the Gaza Strip. It has dramatically reduced the prevalence of infectious diseases, mortality, and illiteracy. Its social services include rebuilding infrastructure and homes that have been destroyed by conflict and providing cash assistance and micro-finance loans for Palestinians whose rights are curtailed and who are denied the right of return to their homeland
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