English
Related papers

Related papers: A Search for Sodium Absorption from Comets Around …

200 papers

We report the detection of 21-cm and H2 absorption lines in the same DLA system (log N(HI)=21.36+-0.10) at zabs=3.17447 towards SDSSJ133724+315254 (z=3.174). We estimate the spin temperature of the gas to be, Ts~600 K, intermediate between…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 R. Srianand , N. Gupta , P. Petitjean , P. Noterdaeme , C. Ledoux

Sulphur is an element which is formed in the alpha-process and is easily measured in the gaseous phase in external galaxies. Since it does not form dust, it is the preferred indicator for alpha-elements, rather than Si or Mg, for which dust…

Astrophysics · Physics 2009-11-13 Elisabetta Caffau , Hans-Guenter Ludwig

We obtained 238 spectra of the close orbiting extrasolar giant planet HD 189733b with resolution R ~ 15,000 during one night of observations with the near infrared spectrograph, NIRSPEC, at the Keck II Telescope. We have searched for…

Transmission spectroscopy is a prime technique to study the chemical composition and structure of exoplanetary atmospheres. Strong excess absorption signals have been detected in the optical Na I D1, 2 Fraunhofer lines during transits of…

Earth and Planetary Astrophysics · Physics 2022-11-30 Hossein Rahmati , Stefan Czesla , Sara Khalafinejad , Paul Mollière

We report the discovery of blue-shifted metastable He I* absorption lines at 3188 A and 3889 A with multiple components on high-resolution spectra (R ~ 60,000) of V1280 Scorpii. Similar multiple absorption lines associated with Na I D…

Solar and Stellar Astrophysics · Physics 2015-06-12 H. Naito , A. Tajitsu , A. Arai , K. Sadakane

New millimeter wave observations of the molecular absorption line system in the gravitational lens to PKS1830-211 at z=0.88582 is presented. Self-calibrated interferometer data shows unequivocally that the previously detected absorption…

Astrophysics · Physics 2009-10-30 Tommy Wiklind , Francoise Combes

The nearby transiting planet HD 189733b was observed during three transits with the ACS camera of the Hubble Space Telescope in spectroscopic mode. The resulting time series of 675 spectra covers the 550-1050 nm range, with a resolution…

Astrophysics · Physics 2009-11-13 F. Pont , H. Knutson , R. L. Gilliland , C. Moutou , D. Charbonneau

We have analyzed the spectrum of the quasar PKS 1232+082 obtained by Petitjean et al. (2000). HD molecular lines are identified in an absorption system at the redshift z=2.3377. The column density of HD molecules in the system is estimated,…

Astrophysics · Physics 2009-11-06 D. Varshalovich , A. Ivanchik , P. Petitjean , R. Srianand , C. Ledoux

We present the results of a search for associated 21 cm HI absorption at redshift 0.42 < z < 1.00 in radio-loud galaxies from three Galaxy And Mass Assembly (GAMA) survey fields. These observations were carried out as part of a pilot survey…

Na I D lines in the spectrum of the young binary KH 15D have been analyzed in detail. We find an excess absorption component that may be attributed to foreground interstellar absorption, and to gas possibly associated with the solids in the…

Solar and Stellar Astrophysics · Physics 2015-05-18 S. M. Lawler , W. Herbst , S. Redfield , C. M. Hamilton , C. M. Johns-Krull , J. N. Winn , J. A. Johnson , R. Mundt

We determine abundances from the absorption spectrum of the magnetic Herbig Ae star HD 190073 (V1295 Aql). The observations are primarily from HARPS spectra obtained at a single epoch. We accept arguments that the presence of numerous…

Solar and Stellar Astrophysics · Physics 2015-06-03 C. R. Cowley , S. Hubrig

Measuring cometary nuclei is notoriously difficult because they are usually unresolved and embedded within bright comae, which hampers direct size measurements even with space telescopes. We present a practical, instrumental method that,…

Instrumentation and Methods for Astrophysics · Physics 2025-11-26 Toni Scarmato

We have obtained high resolution spectra (R = 25000) of an A star over varying airmass to determine the effectiveness of telluric removal in the limit of high signal to noise. The near infra-red line HeI at 2.058 microns, which is a…

Astrophysics · Physics 2015-06-24 M. A. Kenworthy , M. M. Hanson

We report photometric observations for comet C/2012 S1 (ISON) obtained during the time period immediately after discovery (r=6.28 AU) until it moved into solar conjunction in mid-2013 June using the UH2.2m, and Gemini North 8-m telescopes…

Experimental apparatus and measurement technique are described for precision absorption measurements in sodium - noble gas mixtures. The absolute absorption coefficient is measured in the wavelength range from 425 nm to 760 nm with 2%…

Atomic Physics · Physics 2009-11-06 M. Shurgalin , W. H. Parkinson , K. Yoshino , C. Schoene , W. P. Lapatovich

We have observed five sulphur-bearing molecules in foreground diffuse molecular clouds lying along the sight-lines to five bright continuum sources. We have used the GREAT instrument on SOFIA to observe the 1383 GHz $^2\Pi_{3/2} J=5/2-3/2$…

We present a measurement of the deuterium to hydrogen ratio (D/H) in a metal-poor absorption system at redshift $z=2.504$ towards the QSO 1009+2956. We apply the new method of Burles & Tytler (1997) to robustly determine D/H in high…

Astrophysics · Physics 2008-11-26 Scott Burles , David Tytler

We report the detection of variable UV absorption lines in NGC 4395, based on UV observations with the HST STIS carried out in April and July, 2004, as part of a reverberation-mapping campaign. Low-ionization lines of O I, N I, Si II, C II,…

Astrophysics · Physics 2013-04-22 Alexei Baskin , Ari Laor

We present a direct detection of the stellar halo of the edge-on S0 galaxy NGC 3957, using ultra-deep VLT/VIMOS V and R images. This is achieved with a sky subtraction strategy based on infrared techniques. These observations allow us to…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 P. Jablonka , M. Tafelmeyer , F. Courbin , A. M. N Ferguson

Molecular absorption lines of OH (99 lines) and CH (105 lines) are measured for the carbon-enhanced metal-poor star BD+44 493 with [Fe/H]=-3.8. The abundances of oxygen and carbon determined from individual lines based on an 1D-LTE analysis…

Solar and Stellar Astrophysics · Physics 2015-09-30 Wako Aoki