Reinsch, Klaus

[["dc.bibliographiccitation.firstpage","771"],["dc.bibliographiccitation.issue","3"],["dc.bibliographiccitation.journal","Astronomy and Astrophysics"],["dc.bibliographiccitation.lastpage","776"],["dc.bibliographiccitation.volume","481"],["dc.contributor.author","Beuermann, K."],["dc.contributor.author","El Kholy, E."],["dc.contributor.author","Reinsch, K."],["dc.date.accessioned","2019-07-09T11:55:00Z"],["dc.date.available","2019-07-09T11:55:00Z"],["dc.date.issued","2008-04-03"],["dc.description.abstract","Context. Polars (AM Herculis binaries) are a prominent class of bright soft X-ray sources, many of which were discovered with ROSAT. Aims. We present a homogenous analysis of all the pointed ROSAT PSPC observations of polars subdivided into two papers that discuss the prototype polar AM Her in detail and summarize the class properties of all other polars. Methods. We derive the high-state soft X-ray flux and short-term spectral variability of AM Her using a new detector response matrix and a confirmed flux calibration of the ROSAT PSPC below 0.28 keV. Results. The best-fit mean single-blackbody temperature and integrated bright-phase energy flux of AM Her in its April 1991 high state are 7.2\\pm1.0$ eV and \\times 10^{-9}$ erg cm-2 s-1, respectively. The total blackbody flux of a multi-temperature model that fits both the soft X-ray and the fluctuating far-ultraviolet components is \\mathrm{bb}=(4.5\\pm1.5)\\times 10^{-9}$ erg cm-2 s-1. The total accretion luminosity at a distance of 80 pc, \\mathrm{bb}=(2.1\\pm0.7)\\times 10^{33}$ erg s-1, implies an accretion rate of $\\dot M=(2.4\\pm0.8)\\times 10^{-10}$ \\odot\\,\\mathrm{yr}^{-1}$ for an 0.78 \\odot$ white dwarf. The soft X-ray flux displays significant variability on time scales down to 200 ms. Correlated spectral and count-rate variations are seen in flares on time scales down to 1 s, demonstrating the heating and cooling associated with individual accretion events. Conclusions. Our spectral and temporal analysis provides direct evidence for the blobby accretion model and suggests a connection between the soft X-ray and the fluctuating far-ultraviolet components."],["dc.identifier.doi","10.1051/0004-6361:20079335"],["dc.identifier.fs","513461"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/9948"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/60777"],["dc.language.iso","en"],["dc.notes.intern","Merged from goescholar"],["dc.relation.issn","1432-0746"],["dc.relation.orgunit","Fakultät für Physik"],["dc.rights","Goescholar"],["dc.rights.access","openAccess"],["dc.rights.uri","https://goedoc.uni-goettingen.de/licenses"],["dc.title","Soft X-ray spectral variability of AM Herculis"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","199"],["dc.bibliographiccitation.issue","1"],["dc.bibliographiccitation.journal","Astronomy and Astrophysics"],["dc.bibliographiccitation.lastpage","212"],["dc.bibliographiccitation.volume","480"],["dc.contributor.author","Beuermann, K."],["dc.contributor.author","Reinsch, K."],["dc.date.accessioned","2019-07-09T11:54:35Z"],["dc.date.available","2019-07-09T11:54:35Z"],["dc.date.issued","2008"],["dc.description.abstract","Context. EXHya is one of the few double-lined eclipsing cataclysmic variables that allow an accurate measurement of the binary masses. Aims. We analyze orbital phase-resolved UVES/VLT high resolution (λ/Δλ 27 000) spectroscopic observations of EXHya with the aims of deriving the binary masses and obtaining a tomographic image of the illuminated secondary star. Methods. We present a novel method for determining the binary parameters by directly fitting an emission model of the illuminated secondary star to the phase-resolved line profiles of NaIλ8183/8195 in absorption and emission and CaIIλ8498 in emission. Results. The fit to the NaI and CaII line profiles, combined with the published K1, yields a white-dwarf mass M1 = 0.790 ± 0.026 M , a secondary mass M2 = 0.108 ± 0.008 M , and a velocity amplitude of the secondary star K2 = 432.4 ± 4.8 kms−1. The secondary is of spectral type dM5.5 ± 0.5 and has an absolute K-band magnitude of MK = 8.8. Its Roche radius places it on or very close to the main sequence of low-mass stars. It differs from a main sequence star by its illuminated hemisphere that faces the white dwarf. The secondary star contributes only 5% to the observed spin-phase averaged flux at 7500 Å, 7.5% at 8200 Å, and 37% in the K-band. We present images of the secondary star in the light of the NaI doublet and the CaII emission line derived with a simplified version of Roche tomography. Line emission is restricted to the illuminated part of the star, but its distribution differs from that of the incident energy flux. Conclusions. We have discovered narrow spectral lines from the secondary star in EXHya that delineate its orbital motion and allow us to derive accurate masses of both components. The primary mass significantly exceeds recently published values. The secondary is a low-mass main sequence star that displays a rich emission line spectrum on its illuminated side, but lacks chromospheric emission on its dark side."],["dc.identifier.doi","10.1051/0004-6361:20079010"],["dc.identifier.fs","513376"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/9386"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/60685"],["dc.language.iso","en"],["dc.notes.intern","Merged from goescholar"],["dc.relation.issn","1432-0746"],["dc.relation.orgunit","Fakultät für Physik"],["dc.rights","Goescholar"],["dc.rights.access","openAccess"],["dc.rights.uri","https://goedoc.uni-goettingen.de/licenses"],["dc.title","High-resolution spectroscopy of the intermediate polar EX Hydrae"],["dc.title.alternative","I. Kinematic study and Roche tomography"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","1043"],["dc.bibliographiccitation.issue","3"],["dc.bibliographiccitation.journal","Astronomy and Astrophysics"],["dc.bibliographiccitation.lastpage","1046"],["dc.bibliographiccitation.volume","457"],["dc.contributor.author","Reinsch, K."],["dc.contributor.author","Kim, Y."],["dc.contributor.author","Beuermann, K."],["dc.date.accessioned","2019-07-09T11:54:56Z"],["dc.date.available","2019-07-09T11:54:56Z"],["dc.date.issued","2006-10-03"],["dc.description.abstract","Context. The first phase-resolved JHK light curves of the eclipsing polar (AM Herculis binary) V1309Ori are presented and interpreted. Aims. We separate the contributions from the secondary star and from other sources with the aim of determining a photometric distance. Methods. Simple model calculations show that the accretion stream and the cyclotron source on the accreting white dwarf are minor contributors to the infrared light, allowing an accurate determination of spectral type and absolute flux of the secondary star. Results. The unilluminated backside of the secondary star as seen in eclipse has spectral type dM0 to dM0+. Its dereddened magnitude is K = 13.58 at orbital phase φ = 0 (eclipse). Using the calibrated surface brightness of M-stars and the published mass of the secondary, M2 = 0.46 M , we obtain a distance d = 600 ± 25 pc which scales as M1/2 2 . The radius of the Roche-lobe filling secondary exceeds the main-sequence radius of an M0 star by 21+11 −6 %. Conclusions. The debated origin of the infrared light of V1309 Ori has been settled in favor of the secondary star as the main contributor and an accurate distance has been derived that will place estimates of the luminosity and synchronization time scale on a more secure basis."],["dc.identifier.doi","10.1051/0004-6361:20065655"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/9879"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/60760"],["dc.language.iso","en"],["dc.notes.intern","Merged from goescholar"],["dc.relation.issn","1432-0746"],["dc.relation.orgunit","Fakultät für Physik"],["dc.title","The secondary star and distance of the polar V1309 Orionis"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.artnumber","A41"],["dc.bibliographiccitation.journal","Astronomy & Astrophysics"],["dc.bibliographiccitation.volume","543"],["dc.contributor.author","Beuermann, K."],["dc.contributor.author","Burwitz, V."],["dc.contributor.author","Reinsch, K."],["dc.date.accessioned","2019-07-09T11:54:43Z"],["dc.date.available","2019-07-09T11:54:43Z"],["dc.date.issued","2012-06-25"],["dc.description.abstract","We present a simple heuristic model for the time-averaged soft X-ray temperature distribution in the accretion spot on the white dwarf in polars. The model is based on the analysis of the Chandra LETG spectrum of the prototype polar AM Her and involves an exponential distribution of the emitting area vs. blackbody temperature a(T) = a0 exp(−T/T0). With one free parameter besides the normalization, it is mathematically as simple as the single blackbody, but is physically more plausible and fits the soft X-ray and far-ultraviolet spectral fluxes much better. The model yields more reliable values of the wavelength-integrated flux of the soft X-ray component and the implied accretion rate than reported previously."],["dc.format.extent","5"],["dc.identifier.doi","10.1051/0004-6361/201219217"],["dc.identifier.fs","596640"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/9606"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/60712"],["dc.language.iso","en"],["dc.notes.intern","Merged from goescholar"],["dc.relation.issn","1432-0746"],["dc.relation.orgunit","Fakultät für Physik"],["dc.rights","Goescholar"],["dc.rights.access","openAccess"],["dc.rights.uri","https://goedoc.uni-goettingen.de/licenses"],["dc.title","A new soft X-ray spectral model for polars with an application to AM Herculis"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","A91"],["dc.bibliographiccitation.journal","Astronomy and Astrophysics"],["dc.bibliographiccitation.volume","634"],["dc.contributor.author","Beuermann, K."],["dc.contributor.author","Burwitz, V."],["dc.contributor.author","Reinsch, K."],["dc.contributor.author","Schwope, A."],["dc.contributor.author","Thomas, H.-C."],["dc.date.accessioned","2020-12-10T18:11:53Z"],["dc.date.available","2020-12-10T18:11:53Z"],["dc.date.issued","2020"],["dc.identifier.doi","10.1051/0004-6361/201936626"],["dc.identifier.eissn","1432-0746"],["dc.identifier.issn","0004-6361"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/74173"],["dc.notes.intern","DOI Import GROB-354"],["dc.title","Neglected X-ray discovered polars"],["dc.title.alternative","II. The peculiar eclipsing binary HY Eridani"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","A56"],["dc.bibliographiccitation.journal","Astronomy and Astrophysics"],["dc.bibliographiccitation.volume","645"],["dc.contributor.author","Beuermann, K."],["dc.contributor.author","Burwitz, V."],["dc.contributor.author","Reinsch, K."],["dc.contributor.author","Schwope, A."],["dc.contributor.author","Thomas, H.-C."],["dc.date.accessioned","2021-04-14T08:30:15Z"],["dc.date.available","2021-04-14T08:30:15Z"],["dc.date.issued","2021"],["dc.identifier.doi","10.1051/0004-6361/202038598"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/83162"],["dc.notes.intern","DOI Import GROB-399"],["dc.relation.eissn","1432-0746"],["dc.relation.issn","0004-6361"],["dc.title","Neglected X-ray discovered polars"],["dc.title.alternative","III. RX J0154.0–5947, RX J0600.5–2709, RX J0859.1+0537, RX J0953.1+1458, and RX J1002.2–1925"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","A47"],["dc.bibliographiccitation.journal","Astronomy and Astrophysics"],["dc.bibliographiccitation.volume","603"],["dc.contributor.author","Beuermann, K."],["dc.contributor.author","Burwitz, V."],["dc.contributor.author","Reinsch, K."],["dc.contributor.author","Schwope, A."],["dc.contributor.author","Thomas, H.-C."],["dc.date.accessioned","2020-12-10T18:11:34Z"],["dc.date.available","2020-12-10T18:11:34Z"],["dc.date.issued","2017"],["dc.identifier.doi","10.1051/0004-6361/201730800"],["dc.identifier.eissn","1432-0746"],["dc.identifier.issn","0004-6361"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/74068"],["dc.notes.intern","DOI Import GROB-354"],["dc.title","Neglected X-ray discovered polars"],["dc.title.alternative","I. Giant flares in V358 Aquarii"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.artnumber","A104"],["dc.bibliographiccitation.journal","Astronomy & Astrophysics"],["dc.bibliographiccitation.volume","546"],["dc.contributor.author","Thomas, H.-C."],["dc.contributor.author","Beuermann, K."],["dc.contributor.author","Reinsch, K."],["dc.contributor.author","Schwope, A. D."],["dc.contributor.author","Burwitz, V."],["dc.date.accessioned","2019-07-09T11:54:43Z"],["dc.date.available","2019-07-09T11:54:43Z"],["dc.date.issued","2012-10-15"],["dc.description.abstract","We report optical and X-ray observations of the high-field polar RX J1007.5–2017 performed between 1990 and 2012. It has an orbital period of 208.60 min determined from the ellipsoidal modulation of the secondary star in an extended low state. The spectral flux of the dM3 – secondary star yields a distance of 790 ± 105 pc. At low accretion levels, RX J1007.5–2017 exhibits pronounced cyclotron emission lines. The second and third harmonic fall in the optical regime and yield a field strength in the accretion spot of 94 MG. The source is highly variable on a year-to-year basis and was encountered at visual magnitudes between V ∼ 20 and V ∼ 16. In the intermediate state of 1992 and 2000, the soft X-ray luminosity exceeds the sum of the luminosities of the cyclotron source, the hard X-ray source, and the accretion stream by an order of magnitude. An X-ray high state, corresponding to the brightest optical level, has apparently not been observed so far."],["dc.format.extent","9"],["dc.identifier.doi","10.1051/0004-6361/201219878"],["dc.identifier.fs","596644"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/9617"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/60714"],["dc.language.iso","en"],["dc.notes.intern","Merged from goescholar"],["dc.relation.issn","1432-0746"],["dc.relation.orgunit","Fakultät für Physik"],["dc.rights","Goescholar"],["dc.rights.access","openAccess"],["dc.rights.uri","https://goedoc.uni-goettingen.de/licenses"],["dc.title","The high-field polar RX J1007.5–2017"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]