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Related papers: Cataclysmic Variables in Globular Clusters, the Ga…

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Cataclysmic variables (CVs) are tracers of dynamical evolution in globular clusters. A significant sample has been found by the relatively shallow \Halpha surveys conducted with HST thus far in just three globulars: NGC 6397 (3), NGC 6752…

Astrophysics · Physics 2007-05-23 Jonathan E. Grindlay

Based on the current detectable cataclysmic variable (CV) population in Galactic globular clusters (GCs), we show that there is not a clear relation between the number of sources per unit of mass and the stellar encounter rate, the cluster…

Solar and Stellar Astrophysics · Physics 2024-04-08 Liliana Rivera Sandoval , Diogo Belloni , Miriam Ramos Arevalo

Every massive globular cluster (GC) is expected to harbour a significant population of cataclysmic variables (CVs). In this review, I first explain why GC CVs matter astrophysically, how many and what types are theoretically predicted to…

Solar and Stellar Astrophysics · Physics 2012-02-13 Christian Knigge

Cataclysmic variables (CVs) are the most numerous population among the Galactic objects emitting in hard X-rays. Most probably, they are responsible for the extended hard X-ray emission of the Galactic ridge and the central Galactic…

High Energy Astrophysical Phenomena · Physics 2022-02-23 Valery F. Suleimanov , Victor Doroshenko , Klaus Werner

We report on the Chandra ACIS-S3 imaging observation of the globular cluster NGC 6752. We detect 6 X-ray sources within the 10.5" core radius and 13 more within the 115" half-mass radius down to a limiting luminosity of Lx approx 10^{30}…

The study of star clusters plays an important role in our understanding of the Universe since these systems are natural laboratories for testing theories of stellar dynamics and evolution. Particularly, globular clusters (GCs) are one of…

High Energy Astrophysical Phenomena · Physics 2020-08-31 Diogo Belloni , Liliana E. Rivera Sandoval

We measure the spatial distribution and hard X-ray luminosity function of cataclysmic variables (CVs) using the INTEGRAL all-sky survey in the 17-60 keV energy band. The vast majority of the INTEGRAL detected CVs are intermediate polars…

Astrophysics · Physics 2009-11-13 M. Revnivtsev , S. Sazonov , R. Krivonos , H. Ritter , R. Sunyaev

Despite indications that classical cataclysmic variable (CV) stars are rare in globular clusters in general, and in the cluster NGC 6624 in particular, we have serendipitously discovered such a star ~6'' from the cluster center. A Hubble…

Astrophysics · Physics 2009-10-31 Eric W. Deutsch , Bruce Margon , Scott F. Anderson , Ronald A. Downes

We report a $30~\mathrm{ks}$ $Chandra$ ACIS-S survey of the globular cluster M3. Sixteen X-ray sources were detected within the half-light radius ($2.3'$) with $L_X \gtrsim 2.3 \times 10^{31}~\mathrm{erg~s^{-1}}$. We used…

High Energy Astrophysical Phenomena · Physics 2018-12-14 Yue Zhao , Craig O. Heinke , Haldan N. Cohn , Phyillis M. Lugger , Adrienne M. Cool

By studying Swift X-ray spectra of an optically-selected, non-magnetic sample of nearby cataclysmic variables (CVs), we show that there is a population with X-ray luminosity much lower than accounted for in existing studies. We find an…

High Energy Astrophysical Phenomena · Physics 2015-06-12 R. C. Reis , P. J. Wheatley , B. T. Gansicke , J. P. Osborne

NGC 6397 is the closest globular cluster, and hence the ideal place to search for faint stellar populations such as cataclysmic variables (CVs). HST and Chandra observers have identified nine certain and likely CVs in this nearby cluster,…

Astrophysics · Physics 2009-09-29 Michael M. Shara , Sasha Hinkley , David R. Zurek , Christian Knigge , Andrea Dieball

I review recent work on X-ray sources in Galactic globular clusters, identified with low-mass X-ray binaries (LMXBs), cataclysmic variables (CVs), millisecond pulsars (MSPs) and coronally active binaries by Chandra. Faint transient LMXBs…

High Energy Astrophysical Phenomena · Physics 2015-05-27 Craig O. Heinke

Cataclysmic variables (CVs) are compact binary systems in which a white dwarf accretes matter from a Roche-lobe-filling companion star. In this study, we searched for new CVs in the Milky Way in the Chandra Source Catalog v2.0,…

We present constraints on the space densities of both non-magnetic and magnetic cataclysmic variables, and discuss some implications for models of the evolution of CVs. The high predicted non-magnetic CV space density is only consistent…

Solar and Stellar Astrophysics · Physics 2014-07-14 Magaretha L. Pretorius

Cataclysmic Variables (CVs) should be present in large numbers in Globular Clusters (GCs). Numerous low-luminosity X-ray sources identified over the past few years as candidate CVs in GCs support this notion. Yet, very few "cataclysms," the…

Astrophysics · Physics 2009-11-13 Andrej Dobrotka , Jean-Pierre Lasota , Kristen Menou

General Relativity predicts that binary systems of stars produce gravitational waves of significant intensity. Here we are particularly interested in the cataclysmic variable binaries (CVs). These systems emit low frequency gravitational…

Astrophysics · Physics 2007-05-23 M. T. Meliani , J. C. N. de Araujo , O. D. Aguiar

Context. Observations of cataclysmic variables in globular clusters appear to show a dearth of outbursts compared to those observed in the field. A number of explanations have been proposed, including low mass-transfer rates and/or moderate…

High Energy Astrophysical Phenomena · Physics 2015-06-12 Natalie Webb , Mathieu Servillat

The increasing number of synoptic surveys made by small robotic telescopes, such as the photometric Catalina Real-Time Transient Survey (CRTS), represents a unique opportunity for the discovery of variable sources and improves the…

Previous X-ray observations toward the Nuclear Star Cluster (NSC) at the Galactic center have discovered thousands of point sources, most of which were believed to be cataclysmic variables (CVs), i.e., a white dwarf (WD) accreting from a…

High Energy Astrophysical Phenomena · Physics 2019-09-23 Xiao-jie Xu , Zhiyuan Li , Zhenlin Zhu , Zhongqun Cheng , Xiang-dong Li , Zhuo-li Yu

We present evidence that the globular cluster NGC 6397 contains two distinct classes of centrally-concentrated UV-bright stars. Color-magnitude diagrams constructed from U, B, V, and I data obtained with the HST/WFPC2 reveal seven UV-bright…

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