Detection of Water Vapor in the Photosphere of Arcturus

  title={Detection of Water Vapor in the Photosphere of Arcturus},
  author={N. Ryde and D. Lambert and M. Richter and J. Lacy},
  journal={The Astrophysical Journal},
We report detections of pure rotation lines of OH and H2O in the K1.5 III red-giant star Arcturus (α Bootis) using high-resolution, infrared spectra covering the regions 806 −822cm −1 (12.2 −12.4 µm) and 884 −923cm −1 (10.8 −11.3 µm). Arcturus is the hottest star yet to show water-vapor features in its disk-averaged spectrum. We argue that the water vapor lines originate from the photosphere, albeit in the outer layers. We are able to predict the observed strengths of OH and H2O lines… Expand

Tables from this paper

Spatially resolving the thermally inhomogeneous outer atmosphere of the red giant Arcturus in the 2.3 micron CO lines
The outer atmosphere of K giants shows thermally inhomogeneous structures consisting of the hot chromospheric gas and the cool molecular gas. We present spectro-interferometric observations of theExpand
Infrared Spectra and Visibilities as Probes of the Outer Atmospheres of Red Supergiant Stars
In the light of the recent results of the stellar interferometry, we examine the nature of the extra molecular layer outside the photosphere of red supergiant stars, so far studied mostly with theExpand
We derive a self-consistent set of atmospheric parameters and abundances of 17 elements for the red giant star Arcturus: T eff = 4286 ± 30 K, log g = 1.66 ± 0.05, and [Fe/H] = –0.52 ± 0.04. TheExpand
Water vapor on supergiants : The 12 μm texes spectra of μ cephei
Several recent papers have argued for warm, semidetached, molecular layers surrounding red giant and supergiant stars, a concept known as a MOLsphere. Spectroscopic and interferometric analyses haveExpand
Near-Infrared Water Lines in V838 Monocerotis
V838 Monocerotis had an intriguing, nova-like outburst in 2002 January that has subsequently led to several studies of the object. It is now recognized that the outburst of V838 Mon and its evolutionExpand
Water Vapor on Betelgeuse as Revealed by TEXES
The outer atmosphere of the M supergiant Betelgeuse is puzzling. Published observations of different kinds have shed light on different aspects of the atmosphere, but no unified picture has emerged.Expand
The K giant star Arcturus: the hybrid nature of its infrared spectrum
We study infrared spectrum of Arcturus to clarify the nature of the cool component of its atmosphere, referred to as the CO-mosphere, with the use of the IR spectral atlas by Hinkle et al.(1995). TheExpand
W Hya through the eye of Odin. Satellite observations of circumstellar submillimetre H2O line emission
We present Odin observations of the AGB star W Hya in the ground-state transition of ortho-H2O, 110 − 101 ,a t 557 GHz. The line is clearly of circumstellar origin. Radiative transfer modelling ofExpand
Amorphous alumina in the extended atmosphere of alpha Orionis
In this paper we study the extended atmosphere of the late-type supergiant alpha Orionis. Infrared spectroscopy of red supergiants reveals strong molecular bands, some of which do not originate inExpand
Systematic trend of water vapour absorption in red giant atmospheres revealed by high resolution TEXES 12 mu m spectra
Context. The structures of the outer atmospheres of red giants are very complex. Recent interpretations of a range of different observations have led to contradictory views of these regions. It isExpand


Water in K and M giant stars unveiled by ISO
Based on the spectra obtained with Infrared Space Observatory, ISO, we detected the 6.3m bands of water in the late K giant Aldebaran ( Tau) and several early M giant stars (between M0 and M3.5),Expand
Molecules of Non-Photospheric Origin in Red Giants and Supergiants Revealed by the ISO SWS
Overall SEDs based on ISO SWS observations show fair agreement with photospheric model predictions for red (super)giant stars. However, some details of molecular spectra cannot be explained by aExpand
Spectral analysis of water vapour in cool stars
M star spectra, at wavelengths beyond 1.35 µm, are dominated by water vapour yet terrestrial water vapour makes it notoriously difficult to make accurate measurement from ground-based observations.Expand
The nonsolar abundance ratios of Arcturus deduced from spectrum synthesis
Using opacity distribution functions based on a newly expanded atomic and molecular line list, we have calculated a model atmosphere for Arcturus that reproduces the observed flux distribution.Expand
The 3 micron spectrum of R Doradus observed with the ISO-SWS
We have modeled the 2:6{3:7m spectrum of the red semiregular variable R Doradus observed with the Short-Wavelength Spectrometer on board the Infrared Space Observatory. The wavelength resolution ofExpand
The Effective Temperature of Arcturus
We construct an empirical energy distribution for Arcturus from published scans, integrate it to obtain the total flux, and combine the latter with precise interferometric measurements of theExpand
Water in Betelgeuse and Antares.
Absorption lines of hot water have been identified in the infrared spectra of Betelgeuse and Antares near 12.3 micrometers (811 to 819 wavenumbers). Expand
Water on the Early M Supergiant Stars α Orionis and μ Cephei
We reanalyze the spectra of α Ori (M2 Iab) and μ Cep (M2 Ia) observed with the balloon-borne telescope Stratoscope II more than 35 years ago, and we confirm the presence of water in these early MExpand
High-Temperature Rotational Transitions of Water in Sunspot and Laboratory Spectra
Assignments are presented for spectra of hot water obtained in absorption in sunspots and in emission in the laboratory using variational nuclear motion calculations based on a high-level ab initio electronic surface, with allowance for both adiabatic and nonadiabatic corrections to the Born-Oppenheimer approximation. Expand
H2O in stellar atmospheres
We have performed a detailed ab initio computation of the dipole moment surface, the vibrational transition moments, and the spectral lines for the water molecule. A total of 412 vibrationalExpand