A5106263735- Astrophysical Phenomena and Observations
- Particle physics theoretical and experimental studies
- High-Energy Particle Collisions Research
- Pulsars and Gravitational Waves Research
- Gamma-ray bursts and supernovae
- Quantum Chromodynamics and Particle Interactions
- Particle Detector Development and Performance
- Astrophysics and Cosmic Phenomena
- Stellar, planetary, and galactic studies
- Astronomical Observations and Instrumentation
- High-pressure geophysics and materials
- Radiation Detection and Scintillator Technologies
- Astronomy and Astrophysical Research
- Dark Matter and Cosmic Phenomena
- Astrophysics and Star Formation Studies
- Neutrino Physics Research
- Spacecraft Design and Technology
- Astro and Planetary Science
- Geophysics and Gravity Measurements
- Cosmology and Gravitation Theories
- Black Holes and Theoretical Physics
- Satellite Communication Systems
- Mechanics and Biomechanics Studies
- Space exploration and regulation
- Nuclear Physics and Applications
University of Sharjah
2019-2025
Astronomy and Space
2024
Evangelismos Hospital
2021
Istanbul Technical University
2019
Nicolaus Copernicus Astronomical Center
2014-2018
Polish Academy of Sciences
2018
University of Pisa
2016
National Institute for Astrophysics
2016
Max Planck Institute for Extraterrestrial Physics
2007-2016
University of Geneva
2009-2016
The All-sky Medium Energy Gamma-ray Observatory (AMEGO) is a probe class mission concept that will provide essential contributions to multimessenger astrophysics in the late 2020s and beyond. AMEGO combines high sensitivity 200 keV 10 GeV energy range with wide field of view, good spectral resolution, polarization sensitivity. Therefore, key study astrophysical objects have unique signatures gamma-ray regime, such as neutron star mergers, supernovae, flaring active galactic nuclei....
Abstract We present a comprehensive analysis of the optical and infrared (IR) properties high-mass X-ray binary (HMXB) IC 10 X-2, classified as supergiant HMXB superfast transient by previous work. Our regular (daily weekly) observations both Zwicky Transient Facility Las Cumbres Observatory over 5 yr period indicates periodic flares variations in apparent magnitude color with ∼26.5 days—likely orbital this system. The flaring suggests stellar companion is Be star, resulting from increased...
High mass X-ray binaries are among the brightest sources in Milky Way, as well nearby Galaxies. Thanks to their highly variable emissions and complex phenomenology, they have attracted interest of high energy astrophysical community since dawn Astronomy. In more recent years, challenged our comprehension physical processes many bands, ranging from infrared very energies. this review, we provide a broad but concise summary dominating emission across virtually whole electromagnetic spectrum....
A population of obscured supergiant High Mass X-ray Binaries (sgHMXBs) has been discovered by INTEGRAL. wind tomography IGR J17252-3616 inferred a slow velocity to account for the enhanced obscuration. The main goal this study is understand under which conditions high obscuration could occur. We have used an hydrodynamical code simulate flow stellar around neutron star. grid simulations was dependency absorbing column density and light-curves on model parameters. comparison between...
The Meteorite Center at the Sharjah Academy for Astronomy, Space Science and Technology (SAASST) in United Arab Emirates houses a diverse collection of 8,000 specimens, including 805 meteorites various types, such as stony, iron, iron-stony meteorites. These sourced from locations worldwide, include with parent bodies Moon Mars, providing insights into rich diversity meteorite subdivisions their origins. This is only one its kind Gulf region, making it distinctive asset within Middle East...
This study explores the mineralogical and elemental characteristics of Asteroid Vesta by analyzing HED meteorites housed within collection Sharjah Academy for Astronomy, Space Sciences, Technology (SAASST). HED (Howardites, Eucrites, Diogenites) are widely recognized as originating from Vesta, offering valuable insights into its unique composition. The SAASST comprises 32 meteorites, including 6 Eucrites 26 Diogenites. Representative samples each category will undergo detailed...
$Context$: Vela X-1 is the prototype of classical sgHMXB systems. Recent continuous and long monitoring campaigns revealed a large hard X-rays variability amplitude with strong flares off-states. This activity has been interpreted invoking clumpy stellar winds and/or magnetic gating mechanisms. $Aims$: We are probing if observed behaviour could be explained by unstable hydrodynamic flows close to neutron star rather than more exotic phenomena. $Methods$: have used code VH-1 simulate flow...
T CrB is a symbiotic recurrent nova known to exhibit active phases, characterized by apparent increases in the hot component temperature and appearance of flickering, i.e. changes observed flux on time-scale minutes. Historical UV observations have ruled out orbital variability as an explanation for flickering instead suggest caused variable mass transfer. We analysed optical X-ray investigate nature well phases CrB. The spectroscopic photometric confirm that follow two periods ∼1000d...
We present the results of our search for optical counterparts to high-mass X-ray transient sources discovered by various missions. obtained CCD images fields through BVR and Halpha filters in order identify early-type stars R-Halpha versus B-V colour-colour diagram. also medium-resolution spectroscopy candidates confirm presence Hαemission perform spectral classification. report on discovery two sources: XTE J1858+034 IGR J01363+6610, follow-up observations another two, newly identified...
We simulate an oscillating purely hydrodynamical torus with constant specific angular mo- mentum around a Schwarzschild black hole. The goal is to search for quasi-periodic oscil- lations (QPOs) in the light curve of torus. initial setup subjected radial, vertical and diagonal (combination radial vertical) velocity perturbations. hydro- dynamical simulations are performed using general relativistic magnetohydrodynamics code Cosmos++ ray-traced GYOTO code. found that horizontal perturbation...
Abstract This study paper reports on two cases of poisoning with the organophosphorus insecticides, fenthion and omethoate. The victims were admitted in Intensive Care Unit (ICU) a few hours after ingestion insecticides. They received appropriate treatment for organophosphorous (gastric lavage, activated charcoal, atropine pralidoxime) supportive care. Both patients survived. Organophosphate blood levels determined admission (fenthion 2.9 (ig/ml, omethoate 1.6 Hg/ml) during hospitalisation...
Our goal is to understand the specificities of highly absorbed sgHMXB and in particular companion stellar wind, thought be responsible for strong absorption. We have monitored IGR J17252-3616, a system featuring eclipses, with XMM-Newton study vari- ability column density Fe K{\alpha} emission line along orbit during eclipses. also built 3D model structure wind reproduce observed variability. first derived refined orbital solution from INTEGRAL, RXTE XMM data. The monitoring campaign...
Aims. The early acceleration of stellar winds in massive stars is poorly constrained. scattering hard X-ray photons emitted by the pulsar high-mass binary Vela X-1 can be used to probe wind velocity and density profile close surface its supergiant companion HD 77581.
Supergiant X-ray binaries usually comprise a neutron star accreting from the wind of OB supergiant companion. They are classified as classical systems and fast transients (SFXTs). The different behavior these sub-classes sources in X-rays, with SFXTs displaying much more pronounced variability, is (at least) partly ascribed to physical properties massive clumpy stellar wind. In case SFXTs, systematic investigation effects clumps on flares/outbursts has been reported by Bozzo et al. (2017)...
In this paper we report on a long multi-wavelength observational campaign of the supergiant fast X-ray transient prototype IGR J17544-2619. A 150 ks-long observation was carried out simultaneously with XMM-Newton and NuSTAR, catching source in an initial faint state then undergoing bright outburst lasting about 7 ks. We studied spectral variability during quiescence by using thermal bulk Comptonization model that is typically adopted to describe energy distribution young pulsars high mass...
We take advantage of the high sensitivity IBIS/ISGRI telescope and improvements in data analysis software to investigate nature still poorly known X-ray source AX J1910.7+0917, search for close-by previously undetected objects. analyze all publicly available INTEGRAL together with a number archival observations that were carried out direction Chandra, XMM-Newton, ASCA. In field-of-view around we discovered three new sources: IGR J19173+0747, J19294+1327 J19149+1036; latter is positionally...
<i>Aims. <i/>Soft X-ray excesses have been detected in several Be/X-ray binaries and interpreted as the signature of hard reprocessing inner accretion disk. The system XMMU J054134.7-682550, located LMC, featured a giant Type II outburst August 2007. geometry this can be understood by studying response soft excess emission to pulses.<i>Methods. <i/>We analyzed series simultaneous observations obtained with XMM-Newton/EPIC-MOS RXTE/PCA order derive spectral temporal characteristics system,...
Supergiant High Mass X-ray Binary systems (sgHMXBs) consist of a massive, late type, star and neutron star. The massive stars exhibits strong, radiatively driven, stellar winds. Wind accretion onto compact object triggers emission, which alters the wind significantly. Hydrodynamic simulation has been used to study - interaction it two sgHMXBs: i) A heavily obscured sgHMXB (IGR J17252–3616) discovered by INTEGRAL. To account for observable quantities (i.e., absorbing column density) we have...
The Tile Calorimeter, which constitutes the central section of ATLAS hadronic calorimeter, is a non-compensating sampling device made iron and scintillating tiles. construction phase calorimeter nearly complete, most effort now directed toward final assembly commissioning in underground experimental hall. layout tasks carried out during are described, first with brief reminder requirements that drove design. During last few years comprehensive test-beam program has been followed order to...
We report on all the INTEGRAL and Swift data collected during first outburst observed from IGR J18179-1621. The broad-band spectral analysis showed that X-ray emission source is heavily absorbed (NH ≃ 1023 cm-2), well-described by a flat power-law with high energy rollover (cutoff 9−12 keV, e-folding 4−7 keV). found some evidence of cyclotron absorption feature at 22 ± 1 keV. Together pulsations 11.8 s discovered in XRT data, this would suggest J18179-1621 an obscured, magnetized, accreting...
Context.Classical novae are quite frequent in M 31. However, very few spectra of 31 have been studied to date, especially during the early decline phase.