Bogazici University
Astrophysics Laboratory
Members
Principal Investigators
Prof. Dr. Enise Nihal Ercan
Prof. Dr. Mehmet Hakan Erkut
Postdocs
Ahlam Farhan
PhD Students
Gökhan Şen
Muhammet Memiç
Sinancan Kara
MSc Students
İsmet Anıl Baloğlu
Binnur Sökmen Şevik
Elif Naz Toktaş
Astrophysics
Our research group has been analyzing the data acquired by both the new generation X-ray observatories currently on mission in orbit around the Earth and the old generation X-ray observation satellites that have accomplished their mission so far. Observations have been initiated in the visual region of the electromagnetic spectrum thanks to the collaboration with a group of domestic and international participants in optical astronomy monitoring programs. In the very short wavelength region of the electromagnetic spectrum, gamma-ray observations have been launched as well. Research in these areas has been deepened by building all necessary infrastructure. Our team conducts both observational and theoretical researches in a variety of different subjects of galactic and extragalactic astronomy and astrophysics such as galaxy clusters, discovery of supernova remnants in nearby galaxies, neutron stars, black holes, dark matter, and other hot topics of astrophysics.
Astrofizik
Dünya yörüngesinde halen görevde bulunan yeni ve görevini tamamlamış eski nesil X-ışın gözlem uydularından alınmış veriler çözümlenmekte ve gökyüzündeki çeşitli X-ışın kaynaklarının fiziksel özelliklerinin anlaşılması doğrultusunda araştırmalar yapılmaktadır. Bir süredir yurtiçi ve yurtdışından katılımcıların da içinde yer aldığı bir grupla optik astronomi gözlemleri sayesinde görsel tayf bölgesi ve ayrıca gama ışınları gibi elektromanyetik ışınımın daha küçük dalgaboylarında da gözlemlere başlanmış ve bu yöndeki araştırmalar her türlü alt yapı da inşa edilerek derinleştirilmiştir. Araştırma grubumuz, galaktik ve ekstra galaktik astronomi-astrofiziğin pek çok değişik alanlarında, örneğin galaksi kümeleri, yakın galaksilerde süpernova kalıntısı keşfi, nötron yıldızları, kara delikler, karanlık madde ve astrofiziğin diğer güncel konularında hem gözlemsel hem de teorik çalışmalar yürütmektedir.
Publications & Presentations
2023
(PUBLICATION) Sercan Çıkıntoğlu, Sinem Şaşmaz, M. Hakan Erkut, K. Yavuz Ekşi "Constraints on models of fallback discs around millisecond magnetars", MNRAS, March 2023
(TALK) Kara, S. "The infalling elliptical galaxy NGC 4552: Chemical composition of the hot atmosphere", LEM Workshop 2023 - CfA Harvard, 27 February - 02 March 2023 (virtual), Cambridge - USA
(TALK) Kara, S. "The infalling elliptical galaxy NGC 4552: Chemical composition of the hot atmosphere", HERA Workshop 2023 - Max Planck Institute for extraterrestrial Physics, 27 February - 03 March 2023, Munich - Germany
(PUBLICATION) E. N. Ercan, E. Aktekin, H. Bakis, M.H. Erkut, A. S. Ercan; "Discovery of an optical counterpart of the X-ray source NuSTAR J053449+2126.0: A transient new-type quasar with a high redshift", 17 February 2023
2022
(PUBLICATION) Aysegul Tumer, Daniel R. Wik, Massimo Gaspari, Hiroki Akamatsu, Niels J. Westergaard, Francesco Tombesi, E. Nihal Ercan; "The NuSTAR, XMM-Newton, and Suzaku view of A3395 at the intercluster filament interface", The Astrophysical Journal, Volume 930, April 2022
(PUBLICATION) M. Hakan Erkut; "Radio luminosity of GLEAM-X J162759.5–523504.3: does it really exceed the spin-down power of the pulsar?", Monthly Notices of the Royal Astronomical Society: Letters, Volume 514, Issue 1, July 2022
(TALK) Kara, S. "NGC 4552'nin kimyasal zenginleşme çalışması" 22. Ulusal Astronomi Kongresi, 05 Eylül 2022, 10 Eylül 2022, Izmir - Turkey
(POSTER) Şen, G. "Abell 3112 Galaksi Kümesinin XMM-newton Gözlemi" 22. Ulusal Astronomi Kongresi, 05 Eylül 2022, 10 Eylül 2022, Izmir - Turkey
(POSTER) M Memiç, S Kara, E Nihal Ercan, E Aktekin Çalışkan, "An optical and X-ray search of possible supernova remnants in a nearby galaxy NGC 6946", 44th COSPAR Scientific Assembly, 16-24 July 44, Athens, Greece
(TALK) S Kara, T Plsek, K Protusova, JP Breuer, N Werner, F Mernier, N Ercan, "Chemical enrichment study of infalling elliptical galaxy NGC 4552", 44th COSPAR Scientific Assembly. 16-24 July 44, Athens - Greece
(PUBLICATION) A. Farhan, E. N. Ercan, F. Tombesi; "Water megamasers and the central black hole masses in a large sample of galaxies", Advances in Space Research, December 2022
2021
(PUBLICATION) E. N. Ercan, E. Aktekin, "NGC 2366 : An optical search for possible supernova remnants", New Astronomy, Volume 83, February 2021
(PUBLICATION) P. Rosati, S. Basa, A. W. Blain, E. Bozzo, M. Branchesi, L. Christensen, A. Ferrara, A. Gomboc, P. T. O'Brien, J. P. Osborne, A. Rossi, F. Schüssler, M. Spurio, N. Stergioulas, G. Stratta, L. Amati, S. Casewell, R. Ciolfi, G. Ghirlanda, S. Grimm, D. Guetta, J. Harms, E. Le Floc'h, F. Longo, M. Maggiore , et al. "Synergies of THESEUS with the large facilities of the 2030s and guest observer opportunities", Exp Astron 52, 407–437, July 2021
(PUBLICATION) S. Mereghetti, S. Balman, M. Caballero-Garcia, M. Del Santo, V. Doroshenko, M. H. Erkut, L. Hanlon, P. Hoeflich, A. Markowitz, J. P. Osborne, E. Pian, L. Rivera Sandoval, N. Webb, L. Amati, E. Ambrosi, A. P. Beardmore, A. Blain, E. Bozzo, L. Burderi, S. Campana, P. Casella, A. D'Aì, F. D'Ammando, F. De Colle, M. Della Valle , et al. "Time Domain Astronomy with the THESEUS Satellite", Exp Astron, April 2021
2020
(PUBLICATION) M. H. Erkut, M. M. Türkoğlu, K. Y. Ekşi and M. A. Alpar "On the Magnetic Fields, Beaming Fractions, and Fastness Parameters of Pulsating Ultraluminous X-Ray Sources", ApJ 899 97, August 2020
(PUBLICATION) A. Farhan, E. N. Ercan, F. Tombesi; "Tracing circumnuclear dense gas in H2O maser galaxies", Monthly Notices of the Royal Astronomical Society, Volume 499, Issue 1, Pages 1–6, November 2020
Theses Supervised by Prof. Dr E. Nihal Ercan:
MSc Theses:
1. A Study of Low-mass X-ray binaries, 1993, Gökhan Şen
2. ROSAT data analysis of TT Arietis, 1994, Gülnur İkis
3. Ae Aqr: A Dq Her Type Cataclysmic Variable Binary System, 1998 Hakan
Erkut
4. Accretion Disks in Astrophysics Accretion Disks in Astrophysics 1999, Yavuz Ekşi
5. Tv Col: A Dq Her Type Cataclysmic Variable Binary Systems , 1999 Mehmet Cem Çalık
6. Chandra observations of EX Hydrae, 2001 Başak Hakanoğlu
7. XMM Newton data Analysis of Isolated radio Quiet Neutron Stars : 1E 1207.4-5209; RX5 0002+6245; RXJ0822-4300; CXOM JI 85238.4+004020, 2007 Arzu
Mert Ankay
8. The relations between the X-ray Spectral parameters of Gamma Ray Bursts, 2009 Ece Kilerci
9. Dynamical Structure Analysis of Five Binary Galaxy Clusters Observed with XMM Newton X-ray Observatory, 2009, Burcu Beygu
10. Fermi-Lat and Chandra Studies of Shell like Supernova Remnants, 2012 Mustafa Bozkurt
11. XMM Newton Observations of Toothbrush Cluster Of Galaxies, 2019 Sinancan Kara
PhD Theses:
12. “X-Ray Binaries With White Dwarfs”, 2003, Gülnur İkis Gün.
13. “Migration of Giant Planets by Dynamical Friction in an Evolving Planetesimal Disk”, 2003, I.Saffet Yeşilyurt
14. “Star disk interaction and anomalous X-Ray Pulsars’’, ‘2003, K.Yavuz Ekşi
15. “Accretion Disks Around Magnetized Neutron Stars’’, 2005, M. Hakan Erkut
16.“Chemical Enrichment History and Gas Mass Ratio Of Abell 3112’, 2017 Cemile Ezer
17. “Study of the Feedback of Active Galactic Nuclei on the Intra-Cluster Medium of Non-Cool Core Clusters and Their Chemical Enrichment”, Ayşegül Tümer 2019
18.‘’Dense molecular gas tracers in water megamaser galaxies.’’ Ahlam Farhan 2021
19.‘’Super nova Remnants in Nearby Galaxies through Optical and X-ray Observations’’ 2020, Muhammet Memiç ( ongoing)
Ongoing TUBITAK 1001 Projects:
PROJE NO: 122F305
PROJE YÜRÜTÜCÜSÜ: Prof. Dr. ENİSE NİHAL ERCAN
PROJE BAŞLIĞI : Uyarılmış Radyasyon Yayınımı Ile 22 Ghz Su Buharı
Mikrodalga Amplifikasyonu: Yayınım Veren/Vermeyen Galaksilerin Aktif
Galaktik Çekirdek Özelliklerinin Karşılaştırması
PROJE EKİBİ: Dr.Öğretim Üyesi Murat Hüdaverdi (Yıldız Teknik Üniv.) ,
Prof.Dr. Yüksel Karataş (İstanbul Üniv). Dr. Ahlam Farhan