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Journal ArticleDOI

HITEMP, the high-temperature molecular spectroscopic database

TL;DR: In this paper, a new molecular spectroscopic database for high-temperature modeling of the spectra of molecules in the gas phase is described, called HITEMP, which is analogous to the HITRAN database but encompasses many more bands and transitions than HitRAN for the absorbers H2O, CO2, CO, NO and OH.
Abstract: A new molecular spectroscopic database for high-temperature modeling of the spectra of molecules in the gas phase is described. This database, called HITEMP, is analogous to the HITRAN database but encompasses many more bands and transitions than HITRAN for the absorbers H2O, CO2, CO, NO, and OH. HITEMP provides users with a powerful tool for a great many applications: astrophysics, planetary and stellar atmospheres, industrial processes, surveillance, non-local thermodynamic equilibrium problems, and investigating molecular interactions, to name a few. The sources and implementation of the spectroscopic parameters incorporated into HITEMP are discussed.
Citations
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Journal ArticleDOI
TL;DR: In this article, an updated 1D radiative-convective, cloud-free climate model is used to obtain new estimates for HZ widths around F, G, K, and M stars.
Abstract: Identifying terrestrial planets in the habitable zones (HZs) of other stars is one of the primary goals of ongoing radial velocity (RV) and transit exoplanet surveys and proposed future space missions. Most current estimates of the boundaries of the HZ are based on one-dimensional (1D), cloud-free, climate model calculations by Kasting et?al. However, this model used band models that were based on older HITRAN and HITEMP line-by-line databases. The inner edge of the HZ in the Kasting et?al. model was determined by loss of water, and the outer edge was determined by the maximum greenhouse provided by a CO2 atmosphere. A conservative estimate for the width of the HZ from this model in our solar system is 0.95-1.67?AU. Here an updated 1D radiative-convective, cloud-free climate model is used to obtain new estimates for HZ widths around F, G, K, and M stars. New H2O and CO2 absorption coefficients, derived from the HITRAN 2008 and HITEMP 2010 line-by-line databases, are important improvements to the climate model. According to the new model, the water-loss (inner HZ) and maximum greenhouse (outer HZ) limits for our solar system are at 0.99 and 1.70?AU, respectively, suggesting that the present Earth lies near the inner edge. Additional calculations are performed for stars with effective temperatures between 2600 and 7200?K, and the results are presented in parametric form, making them easy to apply to actual stars. The new model indicates that, near the inner edge of the HZ, there is no clear distinction between runaway greenhouse and water-loss limits for stars with T eff 5000?K, which has implications for ongoing planet searches around K and M stars. To assess the potential habitability of extrasolar terrestrial planets, we propose using stellar flux incident on a planet rather than equilibrium temperature. This removes the dependence on planetary (Bond) albedo, which varies depending on the host star's spectral type. We suggest that conservative estimates of the HZ (water-loss and maximum greenhouse limits) should be used for current RV surveys and Kepler mission to obtain a lower limit on ??, so that future flagship missions like TPF-C and Darwin are not undersized. Our model does not include the radiative effects of clouds; thus, the actual HZ boundaries may extend further in both directions than the estimates just given.

1,526 citations


Cites background from "HITEMP, the high-temperature molecu..."

  • ...It is a program to produce high-resolution spectrum of any gas mixture, in any thermodynamical conditions, from line-by-line (LBL) databases such as HITRAN 2008 (Rothman et al. 2009) and HITEMP 20104 (Rothman et al. 2010)....

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Journal ArticleDOI
TL;DR: In this article, the authors present estimates of habitable zones (HZs) around stars with stellar effective temperatures in the range 2600 K-7200 K, for planetary masses between 0.1M and 5M.
Abstract: The ongoing discoveries of extra-solar planets are unveiling a wide range of terrestrial mass (size) planets around their host stars. In this Letter, we present estimates of habitable zones (HZs) around stars with stellar effective temperatures in the range 2600 K-7200 K, for planetary masses between 0.1M and 5M. Assuming H2O-(inner HZ) and CO2-(outer HZ) dominated atmospheres, and scaling the background N2 atmospheric pressure with the radius of the planet, our results indicate that larger planets have wider HZs than do smaller ones. Specifically, with the assumption that smaller planets will have less dense atmospheres, the inner edge of the HZ (runaway greenhouse limit) moves outward (approx.10% lower than Earth flux) for low mass planets due to larger greenhouse effect arising from the increased H2O column depth. For larger planets, the H2O column depth is smaller, and higher temperatures are needed before water vapor completely dominates the outgoing long-wave radiation. Hence the inner edge moves inward (approx.7% higher than Earth's flux). The outer HZ changes little due to the competing effects of the greenhouse effect and an increase in albedo. New, three-dimensional climate model results from other groups are also summarized, and we argue that further, independent studies are needed to verify their predictions. Combined with our previous work, the results presented here provide refined estimates of HZs around main-sequence stars and provide a step toward a more comprehensive analysis of HZs.

596 citations


Additional excerpts

  • ...…Kopparapu et al. (2013) obtained new, improved estimates of the boundaries of the HZ by updating Kasting et al. (1993) model with new H2O and CO2 absorption coefficients from updated line- by-line (LBL) databases such as HITRAN 2008 (Rothman et al. 2009) and HITEMP 2010 (Rothman et al. 2010)....

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Book
01 May 2011
TL;DR: In this paper, the authors present an overview of the solar system and its evolution, including the formation and evolution of stars, asteroids, and free-floating planets, as well as their internal and external structures.
Abstract: 1. Introduction 2. Radial velocities 3. Astrometry 4. Timing 5. Microlensing 6. Transits 7. Imaging 8. Host stars 9. Brown dwarfs and free-floating planets 10. Formation and evolution 11. Interiors and atmospheres 12. The Solar System Appendixes References Index.

527 citations

Journal ArticleDOI
TL;DR: A review of the development, application, and current capabilities of infrared laser-absorption spectroscopy (IR-LAS) sensors for combustion gases can be found in this paper.

438 citations

Journal ArticleDOI
TL;DR: The ExoMol database as mentioned in this paper provides extensive line lists of molecular transitions which are valid over extended temperature ranges, including lifetimes of individual states, temperature-dependent cooling functions, Lande g-factors, partition functions, cross sections, k-coefficients and transition dipoles with phase relations.

421 citations


Cites background from "HITEMP, the high-temperature molecu..."

  • ...The latest, 2010, release [76] only contained data on 5 molecules (OH, NO, CO, H2O and CO2) and improved hot line lists are available for all these molecules; an update to HITEMP is currently in progress [77–79]....

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References
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Journal ArticleDOI
TL;DR: The new HITRAN is greatly extended in terms of accuracy, spectral coverage, additional absorption phenomena, added line-shape formalisms, and validity, and molecules, isotopologues, and perturbing gases have been added that address the issues of atmospheres beyond the Earth.
Abstract: This paper describes the contents of the 2016 edition of the HITRAN molecular spectroscopic compilation. The new edition replaces the previous HITRAN edition of 2012 and its updates during the intervening years. The HITRAN molecular absorption compilation is composed of five major components: the traditional line-by-line spectroscopic parameters required for high-resolution radiative-transfer codes, infrared absorption cross-sections for molecules not yet amenable to representation in a line-by-line form, collision-induced absorption data, aerosol indices of refraction, and general tables such as partition sums that apply globally to the data. The new HITRAN is greatly extended in terms of accuracy, spectral coverage, additional absorption phenomena, added line-shape formalisms, and validity. Moreover, molecules, isotopologues, and perturbing gases have been added that address the issues of atmospheres beyond the Earth. Of considerable note, experimental IR cross-sections for almost 300 additional molecules important in different areas of atmospheric science have been added to the database. The compilation can be accessed through www.hitran.org. Most of the HITRAN data have now been cast into an underlying relational database structure that offers many advantages over the long-standing sequential text-based structure. The new structure empowers the user in many ways. It enables the incorporation of an extended set of fundamental parameters per transition, sophisticated line-shape formalisms, easy user-defined output formats, and very convenient searching, filtering, and plotting of data. A powerful application programming interface making use of structured query language (SQL) features for higher-level applications of HITRAN is also provided.

7,638 citations


"HITEMP, the high-temperature molecu..." refers methods or result in this paper

  • ...The standard database for this work is the HITRAN database [2], which is periodically updated and expanded....

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  • ...Line list comparison between HITEMP2010 and HITRAN [2]....

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  • ...The addition of the collision-induced parameters, namely the air-broadened half-width gair and its temperature-dependence exponent n, the pressure-induced line shift dair, and the self-broadened half-width gself, was accomplished using the slightly extended [2] procedure of Gordon et al....

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Journal ArticleDOI
TL;DR: The HITRAN molecular absorption database as mentioned in this paper contains line parameters for 31 species and their isotopomers that are significant for terrestrial atmospheric studies, including chlorofluorocarbons and other molecular species that are not amenable to line-by-line representation.
Abstract: We describe in this paper the modifications, improvements, and enhancements to the HITRAN molecular absorption database that have occurred in the two editions of 1991 and 1992 The current database includes line parameters for 31 species and their isotopomers that are significant for terrestrial atmospheric studies This line-by-line portion of HITRAN presently contains about 709,000 transitions between 0 and 23,000/cm and contains three molecules not present in earlier versions: COF2, SF6, and H2S The HITRAN compilation has substantially more information on chlorofluorocarbons and other molecular species that exhibit dense spectra which are not amenable to line-by-line representation The user access of the database has been advanced, and new media forms are now available for use on personal computers

1,442 citations

Journal ArticleDOI
TL;DR: In this article, a high quality ab initio potential energy surface (PES) and dipole moment function (DPM) for water has been determined and an adjusted PES is empirically adjusted to improve the agreement between the computed line positions and those from the HITRAN 92 data base with J⩽5 for H216O.
Abstract: We report on the determination of a high quality ab initio potential energy surface (PES) and dipole moment function for water This PES is empirically adjusted to improve the agreement between the computed line positions and those from the HITRAN 92 data base with J⩽5 for H216O The changes in the PES are small, nonetheless including an estimate of core (oxygen 1s) electron correlation greatly improves the agreement with the experiment Using this adjusted PES, we can match 30 092 of the 30 117 transitions in the HITRAN 96 data base for H216O with theoretical lines The 10, 25, 50, 75, and 90 percentiles of the difference between the calculated and tabulated line positions are −011, −004, −001, 002, and 007 cm−1 Nonadiabatic effects are not explicitly included About 3% of the tabulated line positions appear to be incorrect Similar agreement using this adjusted PES is obtained for the 17O and 18O isotopes For HD16O, the agreement is not as good, with a root-mean-square error of 025 cm−1 for line

1,067 citations


"HITEMP, the high-temperature molecu..." refers methods in this paper

  • ...[28] undertook a similar task for data reduction when they were reducing the amount of lines in the AMES database [16] for plume signature computations....

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Journal ArticleDOI
TL;DR: A description and summary of the latest edition of the AFGL HITRAN molecular absorption parameters database are presented and a FORTRAN program is now furnished to allow rapid access to the molecular transitions and for the creation of customized output.
Abstract: A description and summary of the latest edition of the AFGL high-resolution transmission molecular absorption database (HITRAN) parameters are presented. This new database combines the information for the seven principal atmospheric absorbers and twenty-one additional molecular species previously contained on the AFGL atmospheric absorption line parameter compilation and on the trace gas compilation. In addition to updating the parameters on earlier editions of the compilation, new parameters have been added to this edition such as the self-broadened half-width, the temperature dependence of the air-broadened half-width, and the transition probability. The database contains 348,043 entries between 0 and 17,900/cm. A FORTRAN program is now furnished to allow rapid access to the molecular transitions and for the creation of customized output. A separate file of molecular cross sections of 11 heavy molecular species, applicable for qualitative simulation of transmission and emission in the atmosphere, has also been provided.

919 citations


"HITEMP, the high-temperature molecu..." refers background in this paper

  • ...Thus, the HITEMP1995 edition [5] had the 100-character length transition record that was established in 1986 [13]....

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Journal ArticleDOI
TL;DR: The most complete water line list in existence, comprising over 500 million transitions (65 per cent more than any other list) and also the most accurate (over 90 per cent of all known experimental energy levels are within 0.3 cm −1 of the BT2 values) is presented in this article.
Abstract: A computed list of H2 16 O infrared transition frequencies and intensities is presented. The list, BT2, was produced using a discrete variable representation two-step approach for solving the rotation‐vibration nuclear motions. It is the most complete water line list in existence, comprising over 500 million transitions (65 per cent more than any other list) and it is also the most accurate (over 90 per cent of all known experimental energy levels are within 0.3 cm −1 of the BT2 values). Its accuracy has been confirmed by extensive testing against astronomical and laboratory data. The line list has been used to identify individual water lines in a variety of objects including comets, sunspots, a brown dwarf and the nova-like object V838 Mon. Comparison of the observed intensities with those generated by BT2 enables water abundances and temperatures to be derived for these objects. The line list can also be used to provide an opacity for models of the atmospheres of M dwarf stars and assign previously unknown water lines in laboratory

684 citations


"HITEMP, the high-temperature molecu..." refers background or methods in this paper

  • ...[4]) accompanied with a negative sign was used....

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  • ...For example, the recent detection [3] of water in extrasolar planet HD189733b relied heavily on the BT2 line list [4], which is used in the present work as...

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  • ...As discussed in the original BT2 paper [4], even at a temperature of 4000 K, the missing levels above J=50 contribute less than 0....

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  • ...[4], hereafter referred to as BT2, provided the best match with the experimental spectrum....

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