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1

Sasaki, Manami. "X-rays tracing the star formation history of the Magellanic clouds." [S.l.] : [s.n.], 2001. http://deposit.ddb.de/cgi-bin/dokserv?idn=964798824.

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2

Sasaki, Manami. "X-rays tracing the star formation history of the Magellanic clouds." Diss., lmu, 2002. http://nbn-resolving.de/urn:nbn:de:bvb:19-4438.

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3

Güver, Tolga, Feryal Özel, Herman Marshall, Dimitrios Psaltis, Matteo Guainazzi, and Maria Díaz-Trigo. "SYSTEMATIC UNCERTAINTIES IN THE SPECTROSCOPIC MEASUREMENTS OF NEUTRON STAR MASSES AND RADII FROM THERMONUCLEAR X-RAY BURSTS. III. ABSOLUTE FLUX CALIBRATION." IOP PUBLISHING LTD, 2016. http://hdl.handle.net/10150/621974.

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Many techniques for measuring neutron star radii rely on absolute flux measurements in the X-rays. As a result, one of the fundamental uncertainties in these spectroscopic measurements arises from the absolute flux calibrations of the detectors being used. Using the stable X-ray burster, GS 1826-238, and its simultaneous observations by Chandra HETG/ACIS-S and RXTE/PCA as well as by XMM-Newton EPIC-pn and RXTE/PCA, we quantify the degree of uncertainty in the flux calibration by assessing the differences between the measured fluxes during bursts. We find that the RXTE/PCA and the Chandra grati
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4

Gregory, Scott G. "T Tauri stars : mass accretion and X-ray emission." Thesis, St Andrews, 2007. http://hdl.handle.net/10023/336.

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5

Igance, Richard. "Modeling X-ray Emission Line Profiles from Massive Star Winds - A Review." Digital Commons @ East Tennessee State University, 2016. https://dc.etsu.edu/etsu-works/2686.

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The Chandra and XMM-Newton X-ray telescopes have led to numerous advances in the study and understanding of astrophysical X-ray sources. Particularly important has been the much increased spectral resolution of modern X-ray instrumentation. Wind-broadened emission lines have been spectroscopically resolved for many massive stars. This contribution reviews approaches to the modeling of X-ray emission line profile shapes from single stars, including smooth winds, winds with clumping, optically thin versus thick lines, and the effect of a radius-dependent photoabsorption coefficient.
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6

Hubrig, S., M. Schöller, A. Kholtygin, et al. "New Multiwavelength Observations of the Of?p Star CPD -28◦ 2561." Digital Commons @ East Tennessee State University, 2015. https://dc.etsu.edu/etsu-works/6241.

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A rather strong mean longitudinal magnetic field of the order of a few hundred gauss was detected a few years ago in the Of?p star CPD −28° 2561 using FORS2 (FOcal Reducer low dispersion Spectrograph 2) low-resolution spectropolarimetric observations. In this work, we present additional low-resolution spectropolarimetric observations obtained during several weeks in 2013 December using FORS 2 mounted at the 8-m Antu telescope of the Very Large Telescope (VLT). These observations cover a little less than half of the stellar rotation period of 73.41 d mentioned in the literature. The behaviour o
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7

RIGOSELLI, MICHELA. "X-ray emission from the magnetic polar caps of old rotation-powered pulsars." Doctoral thesis, Università degli Studi di Milano-Bicocca, 2020. http://hdl.handle.net/10281/277373.

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Le stelle di neutroni sono il risultato dell'evoluzione di stelle massive dopo l'esplosione di supernova. Il progetto di questa Tesi di PhD consiste nello studio dell'emissione di raggi X da parte di stelle di neutroni isolate di età superiore a 100000 anni. Sono stati analizzati dati provenienti dal satellite XMM-Newton (ESA). Per estrarre la miglior informazione possibile dai dati, ho implementato un metodo di maximum likelihood (ML) e l'ho utilizzato per estrarre spettri e profili pulsati di pulsar vecchie in banda X, che poi sono stati analizzati con raffinati di emissione. La Tesi è strut
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8

Leto, P., Corrado Trigilio, Lidia M. Oskinova, et al. "The Detection of Variable Radio Emission from the Fast Rotating Magnetic Hot B-Star HR 7355 and Evidence for Its X-Ray Aurorae." Digital Commons @ East Tennessee State University, 2017. https://dc.etsu.edu/etsu-works/2695.

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In this paper we investigate the multiwavelengths properties of the magnetic early B-type star HR7355. We present its radio light curves at several frequencies, taken with the Jansky Very Large Array, and X-ray spectra, taken with the XMM X-ray telescope. Modeling of the radio light curves for the Stokes I and V provides a quantitative analysis of the HR7355 magnetosphere. A comparison between HR7355 and a similar analysis for the Ap star CUVir, allows us to study how the different physical parameters of the two stars affect the structure of the respective magnetospheres where the non-thermal
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9

Leto, P., Courtney Trigilio, Lidia M. Oskinova, et al. "A Combined Multiwavelength VLA/ALMA/Chandra Study Unveils the Complex Magnetosphere of the B-Type Star HR5907." Digital Commons @ East Tennessee State University, 2018. https://dc.etsu.edu/etsu-works/2682.

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We present new radio/millimeter measurements of the hot magnetic star HR 5907 obtained with the VLA and ALMA interferometers. We find that HR 5907 is the most radio luminous early type star in the cm–mm band among those presently known. Its multi-wavelength radio light curves are strongly variable with an amplitude that increases with radio frequency. The radio emission can be explained by the populations of the non-thermal electrons accelerated in the current sheets on the outer border of the magnetosphere of this fast-rotating magnetic star. We classify HR 5907 as another member of the growi
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10

Oskinova, Lidia M., Richard Ignace, and D. P. Huenemoerder. "X-ray Diagnostics of Massive Star Winds." Digital Commons @ East Tennessee State University, 2016. https://dc.etsu.edu/etsu-works/2703.

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Observations with powerful X-ray telescopes, such as XMM-Newton and Chandra, significantly advance our understanding of massive stars. Nearly all early-type stars are X-ray sources. Studies of their X-ray emission provide important diagnostics of stellar winds. High-resolution X-ray spectra of O-type stars are well explained when stellar wind clumping is taking into account, providing further support to a modern picture of stellar winds as non-stationary, inhomogeneous outflows. X-ray variability is detected from such winds, on time scales likely associated with stellar rotation. High-resoluti
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11

Krauss, Miriam Ilana. "X-ray spectroscopy of neutron star low-mass X-ray binaries." Thesis, Massachusetts Institute of Technology, 2007. http://hdl.handle.net/1721.1/45408.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Physics, 2007.<br>Includes bibliographical references (p. 133-150).<br>In this thesis, I present work spanning a variety of topics relating to neutron star lowmass X-ray binaries (LMXBs) and utilize spectral information from X-ray observations to further our understanding of these sources. First, I give an overview of important X- ray astrophysics relevant to the work I present in subsequent chapters, as well as information about the X-ray observatories from which I obtained my data. In the next three chapters, I consider spectra
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12

Telleschi, Alessandra Silvia. "Coronal evolution of solar-like stars : X-ray spectroscopy of stars in star-forming regions and the solar neighborhood /." Zürich : ETH, 2007. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=17018.

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13

Oskinova, Lidi, and Richard Igance. "X-ray Diagnostics of Massive Star Winds." Digital Commons @ East Tennessee State University, 2017. https://www.amzn.com/1107170060.

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14

Mineo, Stefano. "X-ray emission from star-forming galaxies." Diss., lmu, 2011. http://nbn-resolving.de/urn:nbn:de:bvb:19-134839.

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15

Thompson, Thomas W. J. "Studies of neutron star X-ray binaries." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2008. http://wwwlib.umi.com/cr/ucsd/fullcit?p3315909.

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Thesis (Ph. D.)--University of California, San Diego, 2008.<br>Title from first page of PDF file (viewed September 4, 2008). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references (p. 204-213).
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16

Medin, Zach, Marina von Steinkirch, Alan C. Calder, Christopher J. Fontes, Chris L. Fryer, and Aimee L. Hungerford. "MODEL ATMOSPHERES FOR X-RAY BURSTING NEUTRON STARS." IOP PUBLISHING LTD, 2016. http://hdl.handle.net/10150/624031.

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The hydrogen and helium accreted by X-ray bursting neutron stars is periodically consumed in runaway thermonuclear reactions that cause the entire surface to glow brightly in X-rays for a few seconds. With models of the emission, the mass and radius of the neutron star can be inferred from the observations. By simultaneously probing neutron star masses and radii, X-ray bursts (XRBs) are one of the strongest diagnostics of the nature of matter at extremely high densities. Accurate determinations of these parameters are difficult, however, due to the highly non-ideal nature of the atmospheres wh
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17

Unger, Sarah. "Multi-wavelength observations of X-ray binaries." Thesis, University of Southampton, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.239646.

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18

Nichols, Joy, D. Huenemoerder, Michael Corcoran та ін. "A Coordinated X-Ray and Optical Campaign of the Nearest Massive Eclipsing Binary, δ Orionis Aa: II. X-Ray Variability". Digital Commons @ East Tennessee State University, 2015. https://dc.etsu.edu/etsu-works/6237.

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We present time-resolved and phase-resolved variability studies of an extensive X-ray high-resolution spectral data set of the δ Ori Aa binary system. The four observations, obtained with Chandra ACIS HETGS, have a total exposure time of ≈ 479 ks and provide nearly complete binary phase coverage. Variability of the total X-ray flux in the range of 5–25 Å is confirmed, with a maximum amplitude of about ±15% within a single ≈ 125 ks observation. Periods of 4.76 and 2.04 days are found in the total X-ray flux, as well as an apparent overall increase in the flux level throughout the nine-day obser
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19

Sanderson, Alastair John Roy. "The X-ray scaling properties of virialized systems." Thesis, University of Birmingham, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.288877.

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20

Massa, Derek, Lidi Oskinova, Raman Prinja та Richard Ignace. "Coordinated UV and X-Ray Spectroscopic Observations of the O-type Giant ξ Per: The Connection between X-Rays and Large-scale Wind Structure". Digital Commons @ East Tennessee State University, 2019. https://dc.etsu.edu/etsu-works/5501.

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We present new, contemporaneous Hubble Space Telescope STIS and XMM-Newton observations of the O7 III(n)((f)) star ξ Per. We supplement the new data with archival IUE spectra, to analyze the variability of the wind lines and X-ray flux of ξ Per. The variable wind of this star is known to have a 2.086-day periodicity. We use a simple, heuristic spot model that fits the low-velocity (near-surface) IUE wind line variability very well, to demonstrate that the low-velocity absorption in the new STIS spectra of N iv λ1718 and Si iv λ1402 vary with the same 2.086-day period. It is remarkable that the
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21

Oskinova, Lidia, Yael Nazé, Helge Todt, et al. "Discovery of X-ray Pulsations from a Massive Star." Digital Commons @ East Tennessee State University, 2014. https://dc.etsu.edu/etsu-works/6240.

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X-ray emission from stars much more massive than the Sun was discovered only 35 years ago. Such stars drive fast stellar winds where shocks can develop, and it is commonly assumed that the X-rays emerge from the shock-heated plasma. Many massive stars additionally pulsate. However, hitherto it was neither theoretically predicted nor observed that these pulsations would affect their X-ray emission. All X-ray pulsars known so far are associated with degenerate objects, either neutron stars or white dwarfs. Here we report the discovery of pulsating X-rays from a non-degenerate object, the massive
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22

Guglielmo, Valentina. "Groups and clusters of galaxies in the XXL survey." Doctoral thesis, Università degli studi di Padova, 2018. http://hdl.handle.net/11577/3421945.

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This thesis presents one of the first census of the properties of galaxies in X-ray selected groups and clusters at intermediate redshift, with the aim of assessing the role of envi- ronment on the galaxy stellar mass assembly, star formation activity and observed stellar population properties. My project is framed in the XXL Survey (Pierre et al. 2016), the largest XMM-Newton programme approved to date, covering two extragalactic regions in the sky of 25 deg2 each one. Extended X-ray sources identified as groups and clusters are spectroscopically confirmed and their main properties are chara
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23

EGRON, ELISE MARIE JEANNE. "Spectral Comparisons of Neutron Star Low-Mass X-Ray Binaries with Black Hole X-Ray Binaries." Doctoral thesis, Università degli Studi di Cagliari, 2013. http://hdl.handle.net/11584/266223.

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The study of high-resolution X-ray spectra of neutron star low-mass X-ray binaries (LMXBs) allows the investigation of the innermost parts of the accretion disk and immediate surroundings of the compact object. The weak magnetic eld of old neutron stars present in such systems allows the accretion disk to approach very close to the compact object, like in black hole X-ray binaries. Using data from X-ray satellites such as XMM-Newton, RXTE, and BeppoSAX, I studied the reection component in two neutron star LMXBs: MXB 1728-34 and 4U 1735-44. I showed that the iron line at 6:4
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24

Ignace, Richard, W. Waldron, and N. Cassinelli. "X-ray Emissions from Clump Bowshocks in Massive Star Winds." Digital Commons @ East Tennessee State University, 2012. https://dc.etsu.edu/etsu-works/6277.

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Clumped structures in wind flows have substantially altered our interpretations of multiwavelength data for understanding mass loss from massive stars. Embedded wind shocks have long been the favored explanation for the hot plasma production and X-ray generation in massive star winds. This contribution reports on line profile shapes fromthe clump bowshock model and summarizes the temperature and emission measure distributions throughout the wind for this model with a focus on results that can be tested against observations.The authors acknowledge funding support for this work from a NASA grant
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25

Dewi, Jasinta Dini Maria. "From Be/X-ray binaries to double neutron star systems." [S.l. : Amsterdam : s.n.] ; Universiteit van Amsterdam [Host], 2003. http://dare.uva.nl/document/91655.

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26

Lin, Jinrong Ph D. Massachusetts Institute of Technology. "Observational and evolutionary studies of neutron star X-ray binaries." Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/77487.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Physics, 2011.<br>Cataloged from PDF version of thesis.<br>Includes bibliographical references (p. 117-125).<br>In this thesis, we present our observational and evolutionary studies of neutron stars in X-ray binary systems. A variety of topics are discussed, which are all related by a single scientific theme, namely, helping to set constraints on the mass-radius relation of neutron stars, and hence on their equations of state (EOS). In Chapter 1 we review the current neutron star masses M and radii R measurement techniques utiliz
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27

Rangelov, Blagoy. "High Mass X-ray Binaries in Nearby Star-forming Galaxies." University of Toledo / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1341608325.

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28

Hartwell, Joanna Mary. "An X-ray study of the impact of star formation : from star clusters to starbursts." Thesis, University of Birmingham, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.403048.

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29

Gonzalez, Marjorie. "X-ray observations of young neutron stars." Thesis, McGill University, 2008. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=18813.

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The extreme physical properties of neutron stars make them efficient emitters at all wavelengths of the electromagnetic spectrum and, traditionally, they have been extensively studied at radio wavelengths. The neutron stars with the highest estimated magnetic fields (so-called "magnetars") have remarkably different characteristics from the rest of the population: they emit no persistent radio emission but show large amounts of high-energy radiation that is thought to be powered by their large magnetic fields. For this thesis we have studied the X-ray emission properties of various types of you
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30

Baskill, Darren Stuart. "X-ray properties of cataclysmic variable stars." Thesis, University of Leicester, 2003. http://hdl.handle.net/2381/30669.

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In this thesis, I study the entire sample of non-magnetic cataclysmic variables observed with the Japanese satellite ASCA, presenting a detailed analysis of the spectral and temporal behaviour of these twenty-nine targets. The spectral analysis indicates that all the targets in the ASCA sample appear to be X-ray under-luminous, with only three possible exceptions. This indicates that energy is being lost from the accretion disk in a non-radiative way. Since a third of the observations require additional absorption above that expected from interstellar alone, both the X-ray under-luminosity and
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31

Balogh, Michael Lajos. "The recent star formation history of galaxies in X-ray clusters." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape9/PQDD_0004/NQ40452.pdf.

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32

Jackson, Floyd Emmanuel. "The properties of discrete X-ray sources in star-forming galaxies." Thesis, Durham University, 2012. http://etheses.dur.ac.uk/3396/.

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Observations of starburst galaxies have revealed a large number of point-like X-ray sources located within these systems, including active galactic nuclei (AGN), X-ray binaries (XRBs), and utraluminous X-ray sources (ULXs). In this thesis we investigate the physical properties of a variety of these objects using both their X-ray emission characteristics and their optical counterparts, in order to better understand the accretion physics of such objects, and the environments in which they are found. This work begins with a study of 3 moderate-redshift (z ~ 0.1) X-ray bright (> 10^42 erg s^-1) ga
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33

Lin, Dacheng. "The accretion process in neutron-star low-mass X-ray binaries." Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/62866.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Physics, 2009.<br>This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.<br>Cataloged from student submitted PDF version of thesis.<br>Includes bibliographical references (p. 207-221).<br>There had been long-standing fundamental problems in the spectral studies of accreting neutron stars (NSs) in low-mass X-ray binaries involving the X-ray spectral decomposition, the relations between subtypes (mainly atoll and Z sources), and the origins
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34

Mulia, Paula Nicole Johns. "A Study of X-ray Binary Populations in Star-Forming Galaxies." University of Toledo / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1544721656145916.

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35

Marini, Bettolo Cecilia. "Performance Studies and Star Tracking for PoGOLite." Doctoral thesis, KTH, Partikel- och astropartikelfysik, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-13015.

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PoGOLite is a balloon-borne experiment, which will study polarized soft γ-ray emissionfrom astrophysical targets in the 25-80 keV energy range by applying well-typephoswich detector technology. Polarized γ-rays are expected from a wide variety of sources including rotation-powered pulsars, accreting black holes and neutron stars,and jet-dominated active galaxies. Polarization measurements provide a powerfulprobe of the γ-ray emission mechanism and the distribution of magnetic and radiation fields around the source. The polarization is determined using Compton scattering and photoelectric absor
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36

Kastner, Joel H., David A. Principe, Kristina Punzi, et al. "M STARS IN THE TW HYA ASSOCIATION: STELLAR X-RAYS AND DISK DISSIPATION." IOP PUBLISHING LTD, 2016. http://hdl.handle.net/10150/621232.

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To investigate the potential connection between the intense X-ray emission from young low-mass stars and the lifetimes of their circumstellar planet-forming disks, we have compiled the X-ray luminosities (L-X) of M stars in the similar to 8 Myr old TW Hya Association (TWA) for which X-ray data are presently available. Our investigation includes analysis of archival Chandra data for the TWA binary systems TWA 8, 9, and 13. Although our study suffers from poor statistics for stars later than M3, we find a trend of decreasing L-X/L-bol with decreasing T-eff for TWA M stars, wherein the earliest-t
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37

Hynes, Robert Ian. "Observations of low mass X-ray transients in outburst." Thesis, n.p, 1999. http://library7.open.ac.uk/abstracts/page.php?thesisid=48.

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Watson, Casey Richard. "The cosmological X-ray evolution of stars, AGN, and galaxies." The Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=osu1148410557.

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39

Mineo, Stefano [Verfasser], and Rashid [Akademischer Betreuer] Sunyaev. "X-ray emission from star-forming galaxies / Stefano Mineo. Betreuer: Rashid Sunyaev." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2011. http://d-nb.info/1015500900/34.

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Zezas, Andreas. "A multiwavelength study of X-ray selected samples of star-forming galaxies." Thesis, University of Leicester, 2001. http://hdl.handle.net/2381/30644.

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This thesis presents a multiwavelength study of two X-ray selected samples of star-forming galaxies. The first sample is defined by the cross-correlation of ROSAT source catalogues with the IRAS Faint Source Catalogue, the Markarian and the Kiso catalogues. The main objective of this project is to investigate whether X-ray luminous star-forming galaxies exist, and if so to quantify their properties. A number of star-forming galaxies with luminosities > 1041erg s--1 are found. Their X-ray luminosity can be explained in terms of a superwind and an X-ray binary component. Moreover, their multi wa
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Kilgard, Roy E. "The X-ray point source population of spiral and star-forming galaxies." Thesis, University of Leicester, 2008. http://hdl.handle.net/2381/4082.

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In this thesis, I study a sample of 11 nearby “normal” spiral galaxies and one starburst galaxy with the Chandra X-ray Observatory and supporting ground-based telescopes, with particular emphasis on the characterisation of the discrete X-ray point source population. Emission from discrete point sources dominates the X-ray flux from spiral galaxies. This survey spans the Hubble sequence for spirals and, hence, a range in star formation, allowing insights into the X-ray source population of many diverse systems. The inclusion of M82, the prototypical starburst galaxy in the nearby universe, allo
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Allen, Jessamyn Leigh. "Accretion flows and neutron star heating in low-mass X-ray binaries." Thesis, Massachusetts Institute of Technology, 2017. http://hdl.handle.net/1721.1/115023.

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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Physics, 2017.<br>Cataloged from PDF version of thesis.<br>Includes bibliographical references (pages 149-166).<br>X-ray binaries are excellent test beds for studies of high-energy accretion flows and the properties of compact objects. Neutron star (NS) low-mass X-ray binaries (LMXBs) vary in brightness by almost 8 orders of magnitude and are hosts to diverse accretion flows, transporting varying amounts of energy and mass toward the central NS, as well as expelling significant mass from the binary. This thesis aims to shed l
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43

Oskinova, L., W. R. Hamann, A. Feldmeier, Richard Ignace, and Y. H. Chu. "Discovery of X-ray Emission from the Wolf-Rayet Star WR 142 of Oxygen Subtype." Digital Commons @ East Tennessee State University, 2009. https://dc.etsu.edu/etsu-works/6260.

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We report the discovery of weak yet hard X-ray emission from the Wolf-Rayet (WR) star WR 142 with the XMM-Newton X-ray telescope. Being of spectral subtype WO2, WR 142 is a massive star in a very advanced evolutionary stage shortly before its explosion as a supernova or gamma-ray burst. This is the first detection of X-ray emission from a WO-type star. We rule out any serendipitous X-ray sources within approximate to 1 '' of WR 142. WR 142 has an X-ray luminosity of L(X) approximate to 7 x 10(30) erg s(-1), which constitutes only less than or similar to 10(-8) of its bolometric luminosity. The
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44

Fleming, Thomas Anthony. "Optical analysis of an x-ray selected sample of stars." Diss., The University of Arizona, 1988. http://hdl.handle.net/10150/184366.

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I analyse an x-ray selected sample of 128 late-type (F-M) stars. These stars were identified as optical counterparts to serendipitous x-ray detections made by the Einstein Observatory Extended Medium Sensitivity Survey. Once identified as x-ray sources, the stars were reobserved with an extensive program of optical observations consisting of high- and low-resolution spectroscopy and photometry. Spectral types, luminosity classes, absolute magnitudes, distances, x-ray luminosities, projected rotation rates (v sin i), radial velocities, and binary status have been determined for the sample. I fi
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Edwards, Philip Gregory. "A search for ultra high energy gamma ray emission from binary X-ray systems." Title page, contents and summary only, 1988. http://web4.library.adelaide.edu.au/theses/09PH/09phe266.pdf.

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46

Hodgkin, Simon T. "EUV and X-ray observations of late-type stars." Thesis, University of Leicester, 1995. http://hdl.handle.net/2381/35914.

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In this thesis I describe a number of projects arising from the ROSAT mission, inspired by a desire to understand better the activity of late-type stars from studies of their coronal EUV and X-ray emission. A brief introduction summarises some of the most important work on cool star coronas. The second chapter describes the mechanisms by which X-rays are produced in coronal plasmas. I also discuss the ROSAT mission, its instrumentation and applicability for observing cool stars. In Chapter 3 I describe the discovery of one of the brightest sources in the EUV sky, the hot white dwarf companion
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47

Huenemoerder, David, L. Oskinova, W. Hamann, Richard Ignace, H. Todt, and W. Waldron. "X-Ray Line Emission from Weak Wind O-Stars." Digital Commons @ East Tennessee State University, 2011. https://dc.etsu.edu/etsu-works/6278.

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The action of X-rays is commonly invoked to explain the wind properties of low-luminosity O-type stars. These stars have significantly smaller mass loss rates than predicted radiation-driven wind theories. In this respect they may resemble the first generation of supermassive stars in the early universe which presumably had weak winds due to their low metallicity. We present the high-resolution X-ray spectrum of a weak-wind star, mu Col, and discuss the potential for X-ray emission line strengths and profiles to discriminate among proposed mechanisms for the generation of X-rays in stellar win
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48

Negueruela, Ignacio. "Observational constraints on Be/x-ray binary models." Thesis, University of Southampton, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.242871.

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49

Naylor, Timothy. "High inclination X-ray and cataclysmic binaries." Thesis, University of Oxford, 1987. http://ora.ox.ac.uk/objects/uuid:c932bc88-4a04-4e08-9ea5-db7178a3dd0b.

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An introduction is given to the fields of X-ray and cataclysmic binaries, low mass X-ray binaries (LMXBs) and globular clusters. New observations of the W Vir star AC5 (=V86) are used show that it is probably the source of Hα emission previous authors have found in core of the globular cluster M15. The first phase resolved optical spectroscopy of AC211, the optical counterpart of the X-ray source in M15, are presented, and its binary period discovered to be 9.l±0.5 hours. A re-analysis of archive ultraviolet (UV) spectra of M15, shows spectral features which are attributed to AC211. These obse
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50

Hamaguchi, Kenji. "X-ray Study of the Intermediate Mass Young Stars Herbig Ae/Be Stars." 京都大学 (Kyoto University), 2001. http://hdl.handle.net/2433/150824.

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