Search Results - "Sonbaş, E"

Optical counterparts of ULXs in NGC 1672 by Allak, S, Akyuz, A, Sonbas, E, Dhuga, K S

“…ABSTRACT In this work, we deploy archival data from Hubble Space Telescope, Chandra, XMM–Newton, and Swift-XRT, to probe the nature of nine candidate…”
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A temporal scale to track the spectral transitions in low-mass X-ray binaries by Sonbas, E, Mohamed, K, Dhuga, K S, Göğüş, E

“…ABSTRACT The results of a temporal analysis of observations for a sample of nine low-mass X-ray binaries (LMXBs) are presented. Of these sources, five host a…”
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GRB 221009A: Discovery of an Exceptionally Rare Nearby and Energetic Gamma-Ray Burst by Williams, Maia A., Kennea, Jamie A., Dichiara, S., Kobayashi, Kohei, Iwakiri, Wataru B., Beardmore, Andrew P., Evans, P. A., Heinz, Sebastian, Lien, Amy, Oates, S. R., Negoro, Hitoshi, Cenko, S. Bradley, Buisson, Douglas J. K., Hartmann, Dieter H., Jaisawal, Gaurava K., Kuin, N. P. M., Lesage, Stephen, Page, Kim L., Parsotan, Tyler, Pasham, Dheeraj R., Sbarufatti, B., Siegel, Michael H., Sugita, Satoshi, Younes, George, Ambrosi, Elena, Arzoumanian, Zaven, Bernardini, M. G., Campana, S., Capalbi, Milvia, Caputo, Regina, D’Aì, Antonino, D’Avanzo, P., D’Elia, V., De Pasquale, Massimiliano, Eyles-Ferris, R. A. J., Ferrara, Elizabeth, Gendreau, Keith C., Gropp, Jeffrey D., Kawai, Nobuyuki, Klingler, Noel, Laha, Sibasish, Melandri, A., Mihara, Tatehiro, Moss, Michael, O’Brien, Paul, Osborne, Julian P., Palmer, David M., Perri, Matteo, Serino, Motoko, Sonbas, E., Stamatikos, Michael, Starling, Rhaana, Tagliaferri, G., Tohuvavohu, Aaron, Zane, Silvia, Ziaeepour, Houri

“…Abstract We report the discovery of the unusually bright long-duration gamma-ray burst (GRB), GRB 221009A, as observed by the Neil Gehrels Swift Observatory…”
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Probing Transit Timing Variations of three hot Jupiters: HATP-36b, HATP-56b, and WASP-52b by Sonbas, E, Karaman, N, Özdönmez, A, Er, H, Dhuga, K S, Göğüş, E, Nasiroglu, I, Zejmo, M

“…ABSTRACT We report the results of new transit observations for the three hot Jupiter-like planets, HATP-36b, HATP-56b, and WASP-52b, respectively. Transit…”
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A minimal time-scale for the spectral states of GX 339−4 by Sonbas, E, Mohamed, K, Dhuga, K S, Tuncer, A, Göğüş, E

“…ABSTRACT Black hole transients are known to undergo spectral transitions that form q-shaped tracks on a hardness intensity diagram. In this work, we use the…”
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The transient ultraluminous X-ray source, ULX-4, in M51 by Allak, S, Akyuz, A, Akkaya Oralhan, İ, Avdan, S, Aksaker, N, Vinokurov, A, Soydugan, F, Sonbas, E, Dhuga, K S

“…ABSTRACT We present the results of a temporal and spectral analysis of the transient source ULX-4 in the galaxy M51. The data used were drawn from…”
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Optical counterparts of two candidate ultraluminous X-ray sources in NGC 4536 by Avdan, H, Sonbas, E, Dhuga, K S, Vinokurov, A, Göğüş, E, Avdan, S, Solovyeva, Y N, Kostenkov, A E, Shablovinskaya, E S, Goktas, D

“…ABSTRACT Archival XMM–Newton, Chandra, and Hubble Space Telescope(HST) data have been used to study the X-ray and optical properties of two candidate…”
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A minimal timescale for the continuum in 4U 1608-52 and Aql X-1 by Mohamed, K, Sonbas, E, Dhuga, K S, Göğüş, E, Tuncer, A, Abd Allah, N N, Ibrahim, A

“…ABSTRACT Similar to black hole X-ray binary transients, hysteresis-like state transitions are also seen in some neutron-star X-ray binaries. Using a method…”
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A Study of Low-mass X-Ray Binaries in the Low-luminosity Regime by Sonbas, E., Dhuga, K. S., Gö ü, E.

“…A recent study of a small sample of X-ray binaries (XRBs) suggests a significant softening of spectra of neutron star (NS) binaries as compared to black hole…”
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X-RAY SOURCES IN THE DWARF SPHEROIDAL GALAXY DRACO by Sonbas, E., Rangelov, B., Kargaltsev, O., Dhuga, K. S., Hare, J., Volkov, I.

“…ABSTRACT We present the spectral analysis of an 87 ks XMM-Newton observation of Draco, a nearby dwarf spheroidal galaxy. Of the approximately 35 robust X-ray…”
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The Bright X-Ray Source in NGC 3413 by Sonbas, E., Dhuga, K. S., Gö ü, E.

“…The emission-line dwarf galaxy NGC 3413 is known to host a bright X-ray source near its optical center. The 0.3-10 keV luminosity of this source is estimated…”
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Host galaxy magnitude of OJ 287 from its colours at minimum light by Valtonen, Mauri J, Dey, Lankeswar, Zola, S, Ciprini, S, Kidger, M, Pursimo, T, Gopakumar, A, Matsumoto, K, Sadakane, K, Caton, D B, Nilsson, K, Komossa, S, Bagaglia, M, Baransky, A, Boumis, P, Boyd, D, Castro-Tirado, A J, Debski, B, Drozdz, M, Escartin Pérez, A, Fiorucci, M, Garcia, F, Gazeas, K, Ghosh, S, Godunova, V, Gomez, J L, Gredel, R, Grupe, D, Haislip, J B, Henning, T, Hurst, G, Janík, J, Kouprianov, V V, Lehto, H, Liakos, A, Mathur, S, Mugrauer, M, Naves Nogues, R, Nucciarelli, G, Ogloza, W, Ojha, D K, Pajdosz-Śmierciak, U, Pascolini, S, Poyner, G, Reichart, D E, Rizzi, N, Roncella, F, Sahu, D K, Sillanpää, A, Simon, A, Siwak, M, Soldán Alfaro, F C, Sonbas, E, Tosti, G, Vasylenko, V, Webb, J R, Zielinski, P

“…ABSTRACT OJ 287 is a BL Lacertae type quasar in which the active galactic nucleus (AGN) outshines the host galaxy by an order of magnitude. The only exception…”
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The lag-luminosity relation in the GRB source frame: an investigation withSwiftBAT bursts by Ukwatta, T. N, Dhuga, K. S, Stamatikos, M, Dermer, C. D, Sakamoto, T, Sonbas, E, Parke, W. C, Maximon, L. C, Linnemann, J. T, Bhat, P. N, Eskandarian, A, Gehrels, N, Abeysekara, A. U, Tollefson, K, Norris, J. P

“…ABSTRACT Spectral lag, which is defined as the difference in time of arrival of high- and low-energy photons, is a common feature in gamma-ray bursts (GRBs)…”
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GAMMA-RAY BURSTS: TEMPORAL SCALES AND THE BULK LORENTZ FACTOR by Sonbas, E., MacLachlan, G. A., Dhuga, K. S., Veres, P., Shenoy, A., Ukwatta, T. N.

“…ABSTRACT For a sample of Swift and Fermi gamma-ray bursts, we show that the minimum variability timescale and the spectral lag of the prompt emission is…”
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The unusual γ-ray burst GRB 101225A from a helium star/neutron star merger at redshift 0.33 by Thöne, C. C., de Ugarte Postigo, A., Fryer, C. L., Page, K. L., Gorosabel, J., Aloy, M. A., Perley, D. A., Kouveliotou, C., Janka, H. T., Mimica, P., Racusin, J. L., Krimm, H., Cummings, J., Oates, S. R., Holland, S. T., Siegel, M. H., De Pasquale, M., Sonbas, E., Im, M., Park, W.-K., Kann, D. A., Guziy, S., García, L. Hernández, Llorente, A., Bundy, K., Choi, C., Jeong, H., Korhonen, H., Kubànek, P., Lim, J., Moskvitin, A., Muñoz-Darias, T., Pak, S., Parrish, I.

“…Long γ-ray bursts (GRBs) are the most dramatic examples of massive stellar deaths, often associated with supernovae 1 . They release ultra-relativistic jets,…”
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Minimum variability time-scales of long and short GRBs by MacLachlan, G. A., Shenoy, A., Sonbas, E., Dhuga, K. S., Cobb, B. E., Ukwatta, T. N., Morris, D. C., Eskandarian, A., Maximon, L. C., Parke, W. C.

“…We have investigated the time variations in the light curves from a sample of long and short Fermi/GBM gamma-ray bursts (GRBs) using an impartial wavelet…”
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The 2017 May 20 stellar occultation by the elongated centaur (95626) 2002 GZ32 by Santos-Sanz, P, Ortiz, J L, Sicardy, B, Benedetti-Rossi, G, Morales, N, Fernández-Valenzuela, E, Duffard, R, Iglesias-Marzoa, R, Lamadrid, J L, Maícas, N, Pérez, L, Gazeas, K, Guirado, J C, Peris, V, Ballesteros, F J, Organero, F, Ana-Hernández, L, Fonseca, F, Alvarez-Candal, A, Jiménez-Teja, Y, Vara-Lubiano, M, Braga-Ribas, F, Camargo, J I B, Desmars, J, Assafin, M, Vieira-Martins, R, Alikakos, J, Boutet, M, Bretton, M, Carbognani, A, Charmandaris, V, Ciabattari, F, Delincak, P, Fuambuena Leiva, A, González, H, Haymes, T, Hellmich, S, Horbowicz, J, Jennings, M, Kattentidt, B, Kiss, Cs, Komžík, R, Lecacheux, J, Marciniak, A, Moindrot, S, Mottola, S, Pal, A, Paschalis, N, Pastor, S, Perello, C, Pribulla, T, Ratinaud, C, Reyes, J A, Sanchez, J, Schnabel, C, Selva, A, Signoret, F, Sonbas, E, Alí-Lagoa, V

“…ABSTRACT We predicted a stellar occultation of the bright star Gaia DR1 4332852996360346368 (UCAC4 385-75921) (mV = 14.0 mag) by the centaur 2002 GZ32 for 2017…”
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The minimum variability time‐scale and its relation to pulse profiles of Fermi GRBs by MacLachlan, G. A., Shenoy, A., Sonbas, E., Dhuga, K. S., Eskandarian, A., Maximon, L. C., Parke, W. C.

“…ABSTRACT We present a direct link between the minimum variability time‐scales extracted through a wavelet decomposition and the rise times of the shortest…”
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The lag-luminosity relation in the GRB source frame: an investigation with Swift BAT bursts by Ukwatta, T. N., Dhuga, K. S., Stamatikos, M., Dermer, C. D., Sakamoto, T., Sonbas, E., Parke, W. C., Maximon, L. C., Linnemann, J. T., Bhat, P. N., Eskandarian, A., Gehrels, N., Abeysekara, A. U., Tollefson, K., Norris, J. P.

“…Spectral lag, which is defined as the difference in time of arrival of high- and low-energy photons, is a common feature in gamma-ray bursts (GRBs). Previous…”
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PROBING CURVATURE EFFECTS IN THE FERMI GRB 110920 by Shenoy, A, SONBAS, E, Dermer, C, Maximon, L C, Dhuga, K S, Bhat, P N, Hakkila, J, Parke, W C, MacLachlan, G A, Eskandarian, Ali, Ukwatta, T N

“…Curvature effects in gamma-ray bursts (GRBs) have long been a source of considerable interest. In a collimated relativistic GRB jet, photons that are off-axis…”
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