Publications

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2020
Khaled, S. A., L. Dam´e, M. A. Semeida, M. Y. Amin, A. Ghitas, S. Yousef, and P. Stoeva, "VARIATIONS OF THE HYDROGEN LYMAN-ALPHA LINE THROUGHOUT SOLAR CYCLE 24 ON ESA/PROBA-2 AND SORCE/SOLSTICE DATA", Comptes rendus de l’Acad´emie bulgare des Sciences, vol. 73, issue 9, pp. 1260-1269, 2020.
Molham, M., N. Clerc, A. Takey, T. Sadibekova, A. B. Morcos, S. Yousef, H. M. Hayman, and M. Li, "X-ray properties of the X-CLASS-redMaPPer galaxy cluster sample: the luminosity–temperature relation", MNRAS , vol. 494, , pp. 161–177, 2020. download-1601460780130.pdf
2019
Latković, O., A. Cséki, C. G. Djurašević, A. Essam, A. S. Hamed, and S. M. Youssef, "Long-term Spot Stability in the Post-common-envelope Binary QS Vir", The Astronomical Journal, vol. 157, issue 3, pp. 1-15, 2019. latkovic_2019_aj_157_3.pdf
NegmEldin, M. A. F., A. E. Elsayed, and S. M. Yousef, "Physical properties of three short period close binaries: KIC 2715417, KIC 6050116 and KIC 6287172", Research in Astronomy and Astrophysics (RAA), vol. 19, issue 2, pp. 25-39, 2019.
2018
Yousef, S., M. A. Semeida, and S. S. Khodairy, "ALERT OF SEVERE EARTHQUAKES WORLDWIDE DUE TO SOLAR FORCING OF VERY WEAK SOLAR CYCLE 24", International Journal of Advances in Science Engineering and Technology, vol. 6, issue 2, pp. 81-85, 2018. sun_earthquake_paper.pdf
Hamed, G. M., M. R. Sanad, S. Yousef, A. Essam, and E. M. Rafy, "Spectral evolution of the two classical novae PW Vul and V1668 Cyg using International Ultraviolet Explorer low-resolution spectra", Astron. Nachr, vol. 339, pp. 173–182, 2018. bhth_d._shhynz_2018.pdf
Hamed, G. M., M. R. Sanad, A. Essam, and S. Yousef, "ULTRAVIOLET SPECTRAL EVOLUTION OF V1974 Cyg USING IUE LOW RESOLUTION SPECTRA", Astrophysics, vol. 61, issue 1, pp. 91-100, 2018. dr._shahenaz.pdf
2017
Yousef, S., R. Mawad, Y. H. O. Algafari, M. Amer, and H. Elfaki, "On the Solar Stimuli that Initiates Makkah Al Mukaramah, Al-Madinah Al-Munawarah and Jeddah Flash Floods", American geophysical union, New Orleans, 11-15 Des., 2017. agu_ipostersessions_-_an_amuze_interactive_system.pdf
Yousef, S., and R. Mawad, "A Proton Flare Triggered the Mw 8.1 Chiapos Mexican Earthquake", American geophysical union, New Orleans, 11-15 Des., 2017. mexican_earthquake_final.pdf
Abseim, A. - A., M. Semeida, M. Saleh, S. Youssef, P. Stoeva, and A. Stoev, "MODIFIED CLOUD METHOD VALIDATION BY DETERMINATION OF PHYSICAL PARAMETERS OF THE SOLAR FLARE ON JUNE 26, 1999", Comptes rendus de l'Academie bulgare des Sciences, vol. 70, issue 6, pp. 839-848, 2017. bhthprof_magdyprof._shahenaz_2017.pdf
2016
Abseim, A. - A. A., M. A. Semeida, and M. Y. Amin, "Modified Cloud Method Validation and Determining Physical Parameters of A Moderate Flare on June 26, 1999", Astronomy and Geophysics 5thAssembly ACAG-5, 17-20 Oct. 2016.
Mawad, R., H. M. Farid, M. Yousef, and S. M. Yousef, "EMPIRICAL CME-SSC LISTING MODEL", The IIER International Conference, 2016. Abstract

The association listing of Coronal Mass Ejection-Storm Sudden Commencement (CME-SSC) events is the aim of
this research. Certain criteria have been put to select the CME-SSC pair events automatically. The travel time of the CME
shock could be estimated from an empirical equation that depends on spatial, temporal, CME angular width and projection
effect conditions. A high correlation was found according to a certain algorithm between the initial speed and the travel time
of the CME shock, R=0.81 with mean arrival time error 16.67 hours for 269 events during the period 1996-2010.

Essam, A., A. S. Hamed, S. M. Youssef, and G. F. Mohamadien, "THE FIRST PHOTOMETRIC ANALYSES OF THE ALGOL BINARY SYSTEMS GSC 04328-02164 AND GSC 03164-01558", Astronomical Journal, vol. 151, issue 91, 2016. Abstract2016_the_first_photometric_analyses__of_the_algol_binary_systems_gsc_04328-02164_-_aj_151_1_19.pdf

The CCD observations for the eclipsing Algol type binary systems GSC 04328-02164 in wideband BVRcIc
filters and GSC 03164-01558 in B and I filters have been analyzed using the PHOEBE package (v 0.31a) to
determine their orbital and physical parameters. The absolute parameters and evolutionary tracks of the two
systems have been determined. The results show that the mass ratio, inclination, distance, and age for the system
GSC 04328-02164 are equal to q=0.674±0.002, i=75.997±0.022, d=375.477±4.299 pc, and
τ=26.76±15.65 ∗ 108 years, respectively. For the other system, GSC 03164-01558, q=0.941±0.006,
i=88.0484±0.030, d=444.651±9.444 pc, and τ=53.63±9.16 ∗ 108 years.

M.A.Wahab, M. M. Shaltoot, S.Youssef, and M.M.Hussein, "Interrelationship between the North Atlantic Oscillation and Solar cycle", INTERNATIONAL JOURNAL OF ADVANCED RESEARCH, vol. 4, issue 1, pp. 261- 266, 2016. Abstract112_ijar-8350.pdf

Understanding the influence of solar variability on the Earth’s climate requires knowledge of solar variability, solar interactions, and the mechanisms explain the response of the Earth’s climate system. The NAO (North Atlantic oscillation) is one of the most dominant modes of global climate variability. Like El Niño, La Niña, and the Southern Oscillation, it is considered as free internal oscillation of the climate system not subjected to external forcing. It is shown, to be linked to energetic solar eruptions. Surprisingly, it turns out that features of solar activity have been related to El Niño and La Niña, also have an significant impact on the NAO. The climate of the Atlantic sector exhibits considerable variability on a wide range of time scales. A substantial portion is associated with the North Atlantic Oscillation (NAO), a hemispheric meridional oscillation as atmospheric mass with centers of action near Iceland and over the subtropical Atlantic. NAO- has a related impacts on winter climate extend from Florida to Greenland and from northwestern Africa over Europe far into northern Asian region.

Mawad, R., M. Yousef, S. M. Yousef, and W. Abdel-Sattar, "QUANTIZATED VARIABILITY OF EARTH’S MAGNETOPAUSE DISTANCE ", World Scientific , vol. 9914, pp. 77-83, 2016. Abstract

The size of the Magnetosphere is calculated during the period 1996-2011. It is discovered that the magnetopause distance D is quantized for D ≥ 8 RE. The magnetic levels are narrow towards the Earth but widely spaced outwards. This quantization disappears in the lower magnetosphere below 7 RE. Once the magnetopause is compressed to 8 -7 RE, multi doors get open which we call the Yousef doors, and the solar wind is injected into the inner magnetosphere then to the ionosphere inducing SID and to the troposphere were it can cause flash floods and seeds of hurricanes.

shahinaz_yousef, and H. Elfaki, Solar Forcing of Weak Solar Cycleson Equatorial African Plateau Lakes, , Germany, Lambert Academic Publishing, 2016.
shahinaz_yousef, and H. Elfaki, Solar Forcing of Weak Solar Cycleson Equatorial African Plateau Lakes, , Germany, Lambert Academic Publishing, 2016.
Mohamed, S. A., S. M. A. Youssef, and M. F. Aboushelib, "STATISTICAL STUDY OF SOME GROUPS OF GALAXIES", International Journal of Advanced Research, vol. 4, issue 4, pp. 1439-1456, 2016. Abstract

In this paper, we apply a clustering technique on de Carvalho et al. catalog of compact groups of galaxies (2005) to test the physical reality of each group. The method is applied on the groupsthat contain five membersonly to classify the relation between each two galaxies in the same group andif they belong to the group or not. The results showed that most of the members are real members in groups while some groups (36 groups) contain one or more attribute discordant galaxies and 20 groups contain 2 sub-groups.

2015
Mawad, R., M. Shaltout, M. Yousef, S. Yousef, and M. Ewaida, "Filaments disappearance in relation to coronal mass ejections during the solar cycle 23", Advances in Space Research, vol. 55, pp. 688–695, 2015. Abstractfilaments_disappearance_-_cme.pdf

We have studied the relationship between filament disappearances with CMEs during solar period 1996–2010. We used the observed
disappearing filaments in Ha data from Meudon given in NOAA, and coronal mass ejections data (CMEs) from SOHO/LASCO. We
obtained 278 CME events (14%) contemporary filament disappearances and CME ejections (from a total of 2018 filament disappearance
events and 15,874 CME events during 1996–2010). We found that the number of associated CME–filament disappearance events
increased with the increase of the solar activity and significantly decreased with quiet sun. The longer filament disappearances have activity
and ability to contemporary association with CMEs more than shorter filament disappearances. The filament disappearance powers
the associated CMEs. CMEs which are associated with filament disappearance are ejected with higher speeds, massive, more energetic,
and smaller angular width compared to non-associated CME events. In addition, the associated filament disappearance CMEs have two
types depending on their duration; short-lived (<9 h), and long-lived (>9 h).

Mawad, R., M. Shaltout, M. Ewaida, M. Yousef, and S. Yousef, "Filaments disappearances in relation to solar flares during the solar cycle 23", Advances in Space Research, vol. 55, pp. 696–704, 2015. Abstractfilaments_disappearance_-_flare.pdf

We studied the association between the filament disappearances and solar flares during 1996–2010; we listed 639 associated filament
disappearances with solar flares under temporal and spatial condition, those particular 639 filament disappearance were associated with
1676 solar flares during the period 1996–2010. The best angular distance between filament disappearances and associated solar flares
ranged between 30 and 60. The number of the associated events increased with increasing solar activity and decreased with quiet
sun. The location of filament disappearances ranges between latitude ±50 and longitude ±70. We found that longer filament
disappearances have activity and ability of contemporary association with flares more than shorter filament disappearance, filament
disappearance powers the associated flares more than non-associated flares events. The associated flares have higher solar flux, longer
duration, and higher importance compared to non-associated flares with filament disappearance. In addition the associated filament
disappearance with flares have two types depending on their duration, short-lived (<9 h), and long-lived (>9 h).

Khodairy, S. S., M. S. E. Hadidy, M. A. Semeida, R. H. A. Hamed, and S. M. A. Youssef, "Relationship between Seismicity and Solar Activities during Solar Cycle 22", International Journal of Advanced Research, vol. 3, issue 2, pp. 9-17, 2015. Abstract

The relations between sunspot numbers and earthquakes (M ≥ 5) and (M ≥ 8), solar 10.7 cm radio flux and earthquakes, solar proton events and earthquakes, sunspots area and earthquakes during solar cycle 22, from 1986 to 1996 have been analyzed in this paper. It has been found that (1) there is an inverse relation between solar activity and earthquakes activity for M ≥ 5 during solar cycle 22. (2) There is a direct relation between solar activity and earthquakes activity for M ≥ 8 during the maximum of solar cycle 22 and an inverse relation between both at the descending phase of the cycle.

2014
Yousef, S., Y. O. h. Algafari, and R. Mawad, "On the solar stimuli that initiate Makkah Al- Mukaramah, Al-Madinah Al-Munawarah and Jeddah flash floods", Journal of. Modern Trends in Physics Research, pp. 122-130, 2014. shhynz_2.pdf
Yousef, S., "A revolutionary theory on the origin of the Moon", Journal of. Modern Trends in Physics Research, pp. 118-121, 2014. shhynz_1.pdf
Yousef, S., M. A. El-Rafy, and H. A. T. A. Hadabi, "Solar forcing on cyclones - case study: Gonu 2007", Journal of. Modern Trends in Physics Research, pp. 111-117, 2014. shhynz_3.pdf
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