Zobrazeno 1 - 10
of 352
pro vyhledávání: '"Zepf S"'
Autor:
Thygesen, E., Sun, Y., Huang, J., Dage, K. C., Zepf, S. E., Kundu, A., Haggard, D., Maccarone, T. J.
Ultraluminous X-ray Sources (ULXs) in globular clusters are low mass X-ray binaries that achieve high X-ray luminosities through a currently uncertain accretion mechanism. Using archival Chandra and Hubble Space Telescope observations, we perform a v
Externí odkaz:
http://arxiv.org/abs/2211.07699
Publikováno v:
MNRAS 485 (2019) 2259-2275
We present an unprecedented, deep study of the primordial low-mass X-ray binary population in an isolated, lower-metallicity environment. We perform followup observations of previously-identified X-ray binary candidates in the Sculptor Dwarf Galaxy b
Externí odkaz:
http://arxiv.org/abs/1902.08635
Autor:
Coulter, D. A., Lehmer, B. D., Eufrasio, R. T., Kundu, A., Maccarone, T., Peacock, M., Hornschemeier, A. E., Basu-Zych, A., Gonzalez, A. H., Maraston, C., Zepf, S. E.
The stellar initial mass function (IMF), which is often assumed to be universal across unresolved stellar populations, has recently been suggested to be "bottom-heavy" for massive ellipticals. In these galaxies, the prevalence of gravity-sensitive ab
Externí odkaz:
http://arxiv.org/abs/1612.05189
Autor:
Brassington, N. J., Fabbiano, G., Zezas, A., Kundu, A., Kim, D. -W., Fragos, T., King, A. R., Pellegrini, S., Trinchieri, G., Zepf, S., Wright, N. J.
We report the spectral and temporal variability properties of 18 candidate transient and potential transient (TC and PTC) sources detected in deep multi-epoch Chandra observation of the nearby elliptical galaxies, NGC 3379, NGC 4278 and NGC 4697. Onl
Externí odkaz:
http://arxiv.org/abs/1206.5304
Autor:
Cho, J., Sharples, R. M., Blakeslee, J. P., Zepf, S. E., Kundu, A., Kim, H. -S., Yoon, S. -J.
Deep images of 10 early-type galaxies in low-density environments have been obtained with the Advanced Camera for Surveys (ACS) on the Hubble Space Telescope. The global properties of the globular cluster (GC) systems of the galaxies have been derive
Externí odkaz:
http://arxiv.org/abs/1204.1054
Autor:
Fabbiano, G., Brassington, N. J., Lentati, L., Angelini, L., Davies, R. L., Gallagher, J., Kalogera, V., Kim, D. -W., King, A. R., Kundu, A., Pellegrini, S., Richings, A. J., Trinchieri, G., Zezas, A., Zepf, S.
We report a detailed spectral analysis of the population of low-mass X-ray binaries (LMXBs) detected in the elliptical galaxy NGC~4278 with Chandra. Seven luminous sources were studied individually, four in globular clusters (GCs), and three in the s
Externí odkaz:
http://arxiv.org/abs/1010.3964
Autor:
Paolillo, M., Puzia, T., Zepf, S. E., Maccarone, T. J., Goudfrooij, P., Kundu, A., Fabbiano, G., Angelini, L.
We present a wide field study of the Globular Clusters/Low Mass X-ray Binaries connection in the cD elliptical NGC1399, combining HST/ACS and Chandra high resolution data. We find evidence that LMXB formation likelihood is influenced by GCs structura
Externí odkaz:
http://arxiv.org/abs/1007.0990
Autor:
Brassington, N. J., Fabbiano, G., Blake, S., Zezas, A., Angelini, L., Davies, R. L., Gallagher, J., Kalogera, V., Kim, D. -W., King, A. R., Kundu, A., Trinchieri, G., Zepf, S.
From a deep multi-epoch Chandra observation of the elliptical galaxy NGC 3379 we report the spectral properties of eight luminous LMXBs (LX>1.2E38 erg/s). We also present a set of spectral simulations, produced to aid the interpretation of low-count
Externí odkaz:
http://arxiv.org/abs/1003.3236
Autor:
Kim, D. -W., Fabbiano, G., Brassington, N. J., Fragos, T., Kalogera, V., Zezas, A., Jordan, A., Sivakoff, G. R., Kundu, A., Zepf, S. E., Angelini, L., Davies, R. L., Gallagher, J. S., Juett, A. M., King, A. R., Pellegrini, S., Sarazin, C. L., Trinchieri, G.
Publikováno v:
Astrophys.J.703:829-844,2009
(abridged) We present a statistical study of the low-mass X-ray binary (LMXB) populations of three nearby, old elliptical galaxies: NGC 3379, NGC 4278, and NGC 4697. With a cumulative ~1 Ms Chandra ACIS observing time, we detect 90-170 LMXBs within t
Externí odkaz:
http://arxiv.org/abs/0902.2343
Autor:
Brassington, N. J., Fabbiano, G., Kim, D. -W., Zezas, A., Zepf, S., Kundu, A., Angelini, L., Davies, R. L., Gallagher, J., Kalogera, V., Fragos, T., King, A. R., Pellegrini, S., Trinchieri, G.
We present the properties of the discrete X-ray sources detected in our monitoring program of the globular cluster (GC) rich elliptical galaxy, NGC 4278, observed with Chandra ACIS-S in six separate pointings, resulting in a co-added exposure of 458-
Externí odkaz:
http://arxiv.org/abs/0902.1652