中文
相关论文

相关论文: Monitoring the Variable Interstellar Absorption to…

200 篇论文

Within the last 10 years, strong, narrow Na I absorption has appeared at v_sun ~ -38 km/s toward the halo star HD 219188; that absorption has continued to strengthen, by a factor 2-3, over the past three years. The line of sight appears to…

天体物理学 · 物理学 2009-11-06 Daniel E. Welty , Edward L. Fitzpatrick

Ultra-high spectral resolution observations of time-varying interstellar absorption towards {\kappa} Vel are reported, using the Ultra-High Resolution Facility on the Anglo-Australian Telescope. Detections of interstellar Ca I, Ca II, K I,…

We present echelle observations of the intrinsic UV absorption lines in the Seyfert galaxy NGC 4151, which were obtained with the Space Telescope Imaging Spectrograph (STIS) on the Hubble Space Telescope on 1999 July 19. The UV continuum…

New optical spectra of Ca II and Na I toward HD 72127AB provide additional evidence for both spatial and temporal variations in the complex interstellar absorption along the two sight lines; archival UV spectra yield information on the…

天体物理学 · 物理学 2009-11-13 Daniel E. Welty , Thuso Simon , L. M. Hobbs

We present an analysis of interstellar Na I (lambda=3302.37\AA, 3302.98\AA), Ti II (lambda=3383.76\AA) and Ca II K (lambda=3933.66\AA) absorption features for 74 sightlines towards O- and B-type stars in the Galactic disc. The data were…

天体物理学 · 物理学 2009-11-11 I. Hunter , J. V. Smoker , F. P. Keenan , C. Ledoux , E. Jehin , R. Cabanac , C. Melo , S. Bagnulo

We present high-resolution (FWHM ~ 0.3-1.5 km/s) spectra of interstellar Ca I absorption toward 30 Galactic stars. Comparisons of the column densities of Ca I, Ca II, K I, and other species -- for individual components identified in the…

天体物理学 · 物理学 2009-11-07 Daniel E. Welty , L. M. Hobbs , Donald C. Morton

We report interstellar C II column densities or upper limits determined from weak absorption of the 2325.4029 A intersystem transition observed in six translucent sightlines with STIS. The sightlines sample a wide range of interstellar…

天体物理学 · 物理学 2009-11-10 U. J. Sofia , J. T. Lauroesch , D. M. Meyer , S. I. B. Cartledge

We present observations of the intrinsic absorption in the Seyfert 1 galaxy NGC 3783 obtained with the STIS/HST and FUSE. We have coadded multiple STIS and FUSE observations to obtain a high S/N averaged spectrum spanning 905-1730 A. The…

We present a study of the abundances and physical conditions in the interstellar gas toward the heavily reddened star HD 192639 [E_(B-V) = 0.64], based on analysis of FUSE and HST/STIS spectra covering the range from 912 to 1361 A. This…

天体物理学 · 物理学 2009-11-07 P. Sonnentrucker , S. D. Friedman , D. E. Welty , D. G. York , T. P. Snow

STIS Echelle observations at a resolution of 10 km/s and UVES/VLT spectroscopy at a resolution of 7 km/s of the luminous QSO HE 0515-4414 (z_em = 1.73, B = 15.0) reveal four intervening O VI absorption systems in the redshift range 1.2 <…

天体物理学 · 物理学 2009-11-06 Dieter Reimers , Robert Baade , Hans-Juergen Hagen , Sebastian Lopez

We discuss the interstellar absorption from many atomic and molecular species seen in high-resolution $HST$/STIS UV and high-S/N optical spectra of the moderately reddened B3-5~V star HD~62542. This remarkable sight line exhibits both very…

星系天体物理 · 物理学 2020-07-08 Daniel E. Welty , Paule Sonnentrucker , Theodore P. Snow , Donald G. York

We show 21-cm line profiles in the direction of stars and extragalactic objects, lying projected on high- and intermediate-velocity clouds (HVCs and IVCs). About half of these are from new data obtained with the Effelsberg 100-m telescope,…

天体物理学 · 物理学 2009-11-06 B. P. Wakker , P. M. W. Kalberla , H. van Woerden , K. S. de Boer , M. E. Putman

We present observations of the UV absorption lines in the Seyfert 1 galaxy NGC 3783, obtained with the medium resolution echelle gratings of the Space Telescope Imaging Spectrograph(STIS) on the Hubble Space Telescope (HST). The spectra…

天体物理学 · 物理学 2009-11-06 S. B. Kraemer , D. M. Crenshaw , J. R. Gabel

(Abridged) We present high-resolution spectra of the interstellar NaI and CaII absorption lines for 3 early-type stars along the line-of-sight towards the Shajn 147 SNR. These are supplemented with far-UV aborption spectra of HD 36665 and…

天体物理学 · 物理学 2009-11-10 S. Sallmen , B. Y. Welsh

We estimate the He II to H I column density ratio, \eta = N(He II)/N(H I), in the intergalactic medium towards the high redshift (z_{em} = 2.885) bright quasar QSO HE 2347-4342 using Voigt-profile fitting of the H I transitions in the Lyman…

宇宙学与河外天体物理 · 物理学 2015-05-19 Sowgat Muzahid , Raghunathan Srianand , Patrick Petitjean

We present HST/STIS (1160--1700A) echelle spectra of the cataclysmic variable (CV) star, QU Car, observed in time-tag mode at three epochs. In catalogues this binary is classified as a nova-like variable. We find evidence of a high-state…

天体物理学 · 物理学 2009-11-07 L. E. Hartley , J. E. Drew , K. S. Long

We present an analysis of interstellar absorption lines in high-resolution optical echelle spectra of SS Cyg obtained during an outburst in 2013 June and in archival Hubble Space Telescope and Far Ultraviolet Spectroscopic Explorer data.…

星系天体物理 · 物理学 2018-06-07 Adam M. Ritchey , George Wallerstein , Jean McKeever

We investigate interstellar absorption from molecular hydrogen (H_2) and metals in an intermediate-velocity cloud (IVC) in the direction of the LMC star Sk -68 80 (HD 36521), based on data from the Far Ultraviolet Spectroscopic Explorer…

天体物理学 · 物理学 2011-05-23 P. Richter , K. R. Sembach , J. C. Howk

We present HST/GHRS echelle observations of multiple interstellar lines of CI, MgI, CrII, and ZnII towards both stars in the mu Cru binary system. Despite large differences in the profiles of the neutral species, no significant variations…

天体物理学 · 物理学 2009-10-30 J. T. Lauroesch , David M. Meyer , John K. Watson , J. C. Blades

The star HD72089 is located behind the Vela supernova remnant and shows a complex array of high and low velocity interstellar absorption features arising from shocked clouds. A spectrum of this star was recorded over the wavelength range…

‹ 上一页 1 2 3 10 下一页 ›