dataesr/scientific-paragraphs-categorization huggingface dataset:
[398]. Uncertainty codes 4 (0. 0 0 01 to 0. 001 cm -1 ) for the line positions and 6 (2-5%) for the line intensities were used in the case of the observed bands. For predicted bands, an uncertainty code 3 (0. 001 to 0. 01 cm -1 ) for the line positions and 4 (10-20%) for the line intensities were adopted. For the JPL line positions, the uncertainty code 5 (0. 0 0 0 01 to 0. 0 0 01 cm -1 ) was used. The labeling V 1 V 2 V 3 V 4 4 5 J ε of the ro-vibrational states has been used in the list; see Jacquemart et al. [397]  for details. In addition, it was discovered that the Q-branch in the ν 2 + 2 ν 4 + ν 5 band near 2. 58 μm was missing from the database. It is now provided based on the model of Lyulin and Perevalov  [395]. In our effort to expand the database to spectral line parameters relevant to the study of planetary atmospheres, we have compiled semi-empirical parameter sets of C 2 H 2 broadened and shifted by the pressure of H 2 , He and CO 2 together with the corresponding temperature dependence of the linewidth.
The observed spectra were reproduced to the residuals of 1% (the reader is referred to Fig. 1  in Ref. [415]  ). It was found that the modeling of the transition intensities required an expansion of the dipole moment operator to higher order; this introduced Herman-Wallis like terms. The line positions and line intensities of the torsional band ( v 4 ) of 12 C 2 H 6 at 35 μm reported by Moazzen-Ahmadi et al. [414]  have been adopted in this update. The uncertainties for line positions are set to no better than 0. 0 0 03 cm -1 (HITRAN code = 4), while those of the line intensities are conservatively set to be 5 to 10% (HITRAN code = 5). For the pressure-broadened widths of the torsional band ( v 4 ) at 35 μm, it should be noted that self-and N 2 -broadened widths are listed in this version, for which we adopted the values calculated by using the linear expressions for ν 9 transitions reported by Devi et al.
[411, 412]  , similar to what was done for C 2 H 6 in the 7-μm region in HITRAN2008  [198]. The uncertainties for widths are conservatively set to 10-20% (HITRAN code = 4). The uncertainties for the temperature dependence exponents of the widths are thought to be 10-25% (HITRAN code = 3). In the near future two minor isotopologues of ethane could be updated in the 12 μm region; one is for the 13 C singly-enriched v 12 band of ethane ( 13 CH 3 12 CH 3 ) at 12. 2 μm measured by Devi et al. [416]  and the other for the singly-deuterated ethane (C 2 H 5 D) at 12. 5 μm studied by Daly et al. [417]. In particular, new studies were reported for 13 CH 3 12 CH 3 in the v 12 band in the 12 μm region by Devi et al. [416]  and in the 7 μm region by di Lauro et al. [418]  for the v 4 , v 9 , v 10 and v 6 + v 11 bands between 1345 and 1557 cm -1.
PH 3 (molecule 28) Phosphine (PH 3 ) is a molecule of interest in astronomy, and its features have long been observed and identified in the spectra of Jupiter and Saturn ( e. g. Refs. [419] [420] [421] [422]  ). Because of its great importance in the Earth's and other planetary atmospheres including the interstellar medium, PH 3 has been the subject of a large number of experimental and theoretical investigations. Far infrared (FIR) line parameters of PH 3 were included for the first time in the HITRAN2012 database  [1]. No updates have been made for any of the spectral line parameters for the infrared (IR) bands of phosphine since the HITRAN2008 database  [198]. After the release of the HITRAN2012 database, there have been a few experimental and theoretical studies reported on phosphine  [423] [424] [425] [426].
These calculations permitted a qualitatively correct agreement with observed data up to the octad range (2733-3660 cm -1 ). An example of the comparison between these ab initio and experimental PNNL spectra  [314]  is given in Fig. 23. The theoretical approach to these variational calculations is described in Rey et al. [430]  and the corresponding line list and ab initio cross-sections in the range (0-70 0 0 cm -1 ) is available in the TheoReTS database  [205]. The ab initio calculations described above (especially line positions) may not be of sufficient quality to model room-temperature high resolution spectra to the HITRAN standard of accuracy. However, they are very helpful in assigning experimental spectra and invaluable in high-temperature simulations and will be considered for inclusion in a future edition of the HITEMP database  [278].
This is fixed in HITRAN2016. The air-broadening coefficients of hydrogen sulfide (H 2 S) in the HITRAN database were set to a constant value, γ air = 0. 0740 cm -1 atm -1 at 296 K, for most of the transitions (since HITRAN2004  [3]  ) Please cite this article as: I. E. [435]  , Sumpf1996-Ref. [436]  , Ball1999-Ref. [440]  , Kissel2002-Ref. [437]  , Ciaffoni2008-Ref. [441]. Right panel: Self-broadening coefficients. Sumpf1996s stands for Ref. [438]. based on the average value of available experimental data while just a few half widths were based on experimental values. For HI-TRAN2016, a thorough survey of measurements of both the airbroadening and self-broadening coefficients of H 2 S has been made  [435] [436] [437] [438]. The report by Tan et al. [439]  describes the results in more detail.
[469]  , and the results of ab initio based calculations including cold and hot bands in the range 0-60 0 0 cm -1 can be found in the TheoReTS database  [205]. These calculations agree well with the new HITRAN2016 line list and experimental PNNL spectra  [314]  in the 10-μm region. New bands of 12 C 13 CH 4 are included in the new version of the database. More precisely, the new parameters which were derived from high-resolution Fourier transform spectra are those of the ν 10 , ν 8, ν 7, ν 4, ν 6 bands, which absorb in the 615-1339 cm -1 spectral region  [472, 473]. Their accuracy can be estimated to be of the order of 0. 6 × 10 -3 cm -1 for the positions  [473]  and 4% for the intensities  [472]. The broadening parameters were determined in the same fashion as for the principal isotopologue described above.
C 4 H 2 (molecule 43) The ν 9 band region (around 220 cm -1 ) and the ν 8 band region (around 650 cm -1 ) of diacetylene, C 4 H 2 , is important in interpreting Titan  [488]  observations. The ν 9 band region has been completely replaced with a new line list derived from a combined analysis presented in Refs. [4 88,4 89 ]. The updated line list provides new intensity for the lines already existing in the database but also includes numerous hot bands. The ν 8 band region was updated by scaling the intensities of all the lines in that region by a factor of 0. 8 based on the recommendation given in Jolly et al. [489]. Finally, the ν 6 + ν 8 region (around 1200 cm -1 ) was introduced into HITRAN for the first time based on the predictions from the global analyses. This band is important in astrophysics as it has been observed in the atmosphere of Titan and the preplanetary nebula SMP LMC 11 with the Spitzer Infrared Spectrograph  [490].
H 2 (molecule 45) Molecular hydrogen (H 2 ) is the most abundant gas in the atmosphere of gaseous giants. It was first introduced in HITRAN2012  [1]. The line list covered the quadrupole-allowed transitions for the H 2 isotopologue and dipole-allowed transitions for HD in their ground electronic states. An update was made for singly-deuterated molecular hydrogen (HD) shortly after the release of the HITRAN2012 database. It was discovered by J. Mendrok (Lulea University of Technology, Kiruna, Sweden) that the abundance of the HD molecule was incorrectly calculated in the original release of HITRAN2012; this issue has now been fixed. The implication was that the intensities of the electric dipole transitions originally reported needed to be multiplied by a factor of two, although it did not affect the Einstein-A coefficients.
In HITRAN2016, a complete dataset of the line-shape parameters for the Hartmann-Tran profile is provided for self-perturbed H 2  [6]. This dataset was determined from the analysis of H 2 experimental spectra. According to the new recommendation adopted in HI-TRAN, these line-shape parameters are stored separately for four different tem perature ranges, see Ref. [6]. For the lines and conditions for which experimental spectra are not available, the lineshape parameters were extrapolated. In the near future we plan to extend HITRAN with the HT line-shape parameters for H 2 perturbed by helium, which will be based on experimentally validated ab initio calculations  [493].
[503]. Also included were 25 pure-rotation transitions observed by Meyer et al. [504]  for which the ab initio intensities of Underwood et al. [503]  were used. SO 3 is a planar, non-polar molecule but with sufficient rotational excitation that the molecule can distort and undergo pure-rotational transitions. A hybrid, empirical ab initio rotational line list for 32 S 16 O 3 has been constructed for this edition of the database. For this, the ground-state rotational constants and centrifugal distortion parameters were taken from the fits to their infrared spectrum given by Ref. [502]  ; these were used to generate a set of vibrational ground-state rotational energies for J up to 85. To ensure that the extrapolation to high-J states is reasonable, a comparison was made between these energy levels and those calculated variationally by Ref.
Absorption cross-sections Apart from the line-by-line spectroscopic absorption parameters discussed in Section 2, the HITRAN database contains information on absorption cross-sections where the line-by-line parameters are absent or incomplete. Usually this takes place for heavy polyatomic molecules (with low-lying vibrational modes) which are difficult for detailed analysis due to the high density of the spectral bands/lines, broadening effects, isomerization, and overall modeling complexity. Knowledge of the spectroscopy of these molecules is important for many purposes, including atmospheric remote sensing, radiative forcing calculations, detection of biomass burning, detection of toxic industrial chemicals (TICs), climate change monitoring, modeling planetary atmospheres, spectral calibration, etc.
The cross-sections come from high-resolution laboratory observations, predominantly from Fourier transform spectrometers. Some of these measurements include small negative values, which for the HITRAN-formatted cross-sections were substituted by zeroes; in these cases we provide all the original crosssections in a supplementary "Alternate" folder, because the negative values provide the user with some information about the noise level in the measurements. The HITRAN2012 edition of the database contained crosssections for about fifty gases. For the HITRAN2016 edition we have increased the amount of gases almost six fold by adding new data in the infrared spectral range. A dedicated paper detailing this update will be published separately. Here we only provide a brief summary and overview tables.
Around 220 molecules of atmospheric, industrial, and remote sensing interests were taken from the quantitative spectroscopy PNNL (Pacific Northwest National Laboratory) database, described in Sharpe et al. [314]. This compilation was updated with 55 molecules from more recent work of Johnson et al. [519]. Twelve of these 55 molcules are new to PNNL. Spectra for these molecules will be indispensable, particularly for biomass burning detection. The PNNL database contains calibration-quality composite spectra given at atmospheric pressure and three temperatures (5 °C, 25 °C, and 50 °C). All these cross-sections were measured using the FT-IR technique with 0. 112 cm -1 spectral resolution on a Bruker IFS 66v/S spectrometer. In addition, a large portion of new molecules of atmospheric interest was taken from the 2013 review by Hodnebrog et al.
The summary on the new and updated compounds divided by categories is presented in Table  9. These categories are implemented in HITRAN online for the convenience of users to browse the data. This summary does not include those compounds that were not updated. For instance, there are no new UV cross-sections that were added; therefore molecules that had only UV crosssections in HITRAN2012 are not included in this table. In Fig. 27  we show an example of the update for the acetaldehyde molecule (CH 3 CHO). The new data were taken from the PNNL database  [314]  , while the data from HITRAN2012 were originally from Tereszchuk and Bernath  [541]. Sixteen cross-section temperature-pressure sets from Ref. [541]  are presented in HI-TRAN2012 in the 240 0-340 0 cm -1 spectral range. These crosssections were calibrated using the PNNL data  [541]  and thus are in a good agreement with the update, in particular for absorption between 6.
If the broadener is not provided, self-broadening is assumed. Both tables contain total pressure of the sample including the buffer gas (where applicable). While the extent of the update of the cross-sectional part of the database is impressive, this section of the database is by no means complete. In the future we plan further revision of high-quality data that become available in the literature and by the facilitation of new experiments. In the near future we also plan to extend the database to include planetary-relevant cross-sections that recently became available, including those given in Refs. [548] [549] [550] [551] [552]. An extensive update of the UV cross-sections is also planned.
Collision-induced absorption Collision-induced absorption (CIA) was first introduced into HI-TRAN in the 2012 edition and was largely based on the data collected in Richard et al. [586]. This section of the database is accessible through ( www. hitran. org/cia ). CIA refers to absorption by transient electric dipoles induced by the interaction between colliding molecules. Due to the short life-time of collision complexes, this typically leads to broad absorption features underlying the much sharper lines due to absorption by isolated molecules. As CIA arises from binary collision complexes, the intensity scales with the number densities of both the absorber and the perturber, i. e. , with the square of the pressure at constant volume mixing ratio. To be completely explicit, the transmittance at wavenumber ν, τ abs-pert ( ν), is related to the collision-induced cross section tabulated in the HITRAN CIA section, k abs-pert ( ν), through -ln τ abs -pert ( ν) = k abs -pert ( ν) ρ abs ρ pert L,  (10)  where ρ abs and ρ pert are the number densities of the absorber and perturber, respectively, and L is the path length.
Oxygen A band in air Collision-induced absorption in the oxygen A band is also of atmospheric interest. In spite of the smaller contribution of CIA in this band, relative to the much stronger magnetic dipole lines, CIA is significant for high-accuracy measurements including airmass calibration of the OCO-2 instrument  [589]. The HITRAN CIA database already contained data for O 2 -O 2 and O 2 -N 2 from Tran et al. [253]  , valid for temperatures between 200 and 300 K. For Please cite this article as: I. E. Gordon   [252]  obtained in a multispectrum fitting approach. Line-byline parameters determined in the same multispectrum fit, are also available in HITRAN2016. Consistent use of both line-by-line and CIA data accurately reproduces the total absorption under atmospheric conditions, and has been shown to reduce systematic errors in atmospheric retrievals  [252].
The imaginary refractive index m imag determines the amount of light absorption in a medium, attenuating the light intensity by exp( -4 π m imag x/ λ) along a path of distance x. New HITRAN2016 indices include refractive indices associated with exoplanet atmospheres. Indices (see Table  12  ) of materials which condense out at temperatures from 1725 K (e. g. SiO 2 ) to 700 K (e. g. ZnS) include most of the condensates tabulated  HITRAN2016 extends the HITRAN-RI program  [635]  that resides on the HITRAN website by including the exoplanet indices. HITRAN-RI is written in the IDL (Interactive Design Language) and Fortran 90 programming languages, and applies the Bohren-Huffman  [633]  Mie code. The user specifies in a user-edited ASCII file the particle composition (refractive index), wavelength range, and log-normal particle size distribution.
ARTICLE IN PRESS JID: JQSRT [m5G;  August 21, 2017; 14:18 ]  in subdirectories in ASCII and NetCDF formats. The user can use the ASCII files to quickly look up the real and imaginary indices at a specific wavelength, while the HITRAN-RI program accesses the netCDF files. HITRAN-RI allows the user to read in user-specified refractive indices. The source code of HITRAN-RI can also be modified and added to by the user. 6. Global data and software 6. 1. Database structure and interface ( www. hitran. org) Since June 2015, users have been able to access the HITRAN line-by-line data not only by downloading them in the traditional ASCII 160-character (. par) format from the ftp site, but also through the easy-to-use interface HITRAN online, available at www. hitran. org. Cross sections can also be accessed through this dynamic interface, while CIA and aerosols sections of the database are also accessible, though so far only as static files.
This new tool (described in Hill et al. [2]  ) allows custom filtering and selection of molecules and their isotopologues in the wavenumber region of interest. The default output format is still. par, but users are given an opportunity to create their own, customized output formats, including the HDF5 format widely used by NASA scientists. The flexibility of the formats is achieved due to the fact that the database is cast into a relational format  [236]  : it is now a compilation of tables of parameters and metadata that are interconnected and searchable using Structured Query Language (SQL) (see Refs. [2]  and  [236]  for details). This new flexible database format offers many advantages over the static fixed-width ASCII files. Indeed, we have now introduced non-Voigt line shapes  [6]  , broadening parameters by perturbing gases other than air or self  [4]  , and other parameters that are important for accurate atmospheric retrievals.
HITRAN application programming interface (HAPI) The HITRAN Application Programming Interface (HAPI) is a free open source Python module (library) which provides a set of tools for working with structured spectroscopic data from different sources. It is described in detail in Ref. [5]. Here we give a brief overview of its features. Originally created as an extension of the HITRAN online web interface  [2]  to allow users sophisticated calculations and manipulations with the HITRAN data on their computers, HAPI can handle user-supplied custom data in a flexible way and fully sup-ports the HITRAN online data scheme and formats of the HITRAN  [1]  database. The principal aim of HAPI is facilitating physically-sound interpretation of observations and more realistic models for a wide variety of applications such as astrophysics, planetary science, climate simulations, remote sensing, theoretical spectroscopy, and data mining.
Having such a tool is important in particular to prevent possible errors in radiative-transfer calculations caused by misuse of spectroscopic tools and databases (see example discussed in Ref. [636]  for instance). The HAPI package can be obtained via the HITRAN online website ( http://hitran. org/hapi ) or from the Zenodo community ( http: //zenodo. org/communities/hapi/about/ ). The current version (1. 1) is distributed under a permissive open source license (MIT). Additional links can be found on the official HITRAN site. HAPI consists of two major parts. First, it has a simple built-in database management system written in pure Python, which gives a capability of data processing and filtering. Second, HAPI incorporates a set of tools for spectra simulation accounting for the temperature, pressure, optical path length, and instrument properties.
In more detail, the HAPI features are as follows: • Support for standard HITRAN parameters given in "160character" or ". par" format which is described in Ref. [3] , • Support for the newly added types of parameters such as foreign broadenings and shifts, speed dependencies for non-Voigt profiles, line mixing coefficients, etc. • Communication with the HITRAN online web interface using the REST HTTP protocol in order to get the most up-to-date HITRAN data, • Python implementations for line profiles including the partially correlated quadratic speed-dependent hard collision model (Hartmann-Tran profile  [7, 8, 13, 14]  ), • Python implementation of the Total Internal Partition Sums (based on TIPS-2011  [112]  and incorporating a large update outlined in this paper), • High-resolution single-layer spectra simulation accounting for pressure, temperature, optical path length and instrument function.
• Capability of extending the HAPI functionality by adding custom line shapes, partition sums, instrumental functions, environment dependences, and radiative-transfer code. • Compatibility with a large set of third-party libraries in Python, C/C ++ , Java etc… In the near future, in order to improve the simulation of the absorption cross sections, it is planned to include the full relaxation matrix calculation for line mixing for a number of molecules of atmospheric importance  [117, 238, 239]. Inclusion of the line mixing in the calculation is expected to enable sub-percent accuracy (provided other parameters are known very accurately) for bands of atmospheric gases to better satisfy highly-precise ground and satellite measurements. Groups of related parameters such as those relating to the HT profile in different temperature regions are selected from a separate set of overlay panels in the HITRAN online interface.
When one or more temperature groups are chosen, the three "Common parameters" are also automatically selected. Conversely, these common parameters are removed from the selection when no temperature group is chosen for this profile. Different broadening species are presented on separate panels, and may be selected from the labeled tabs at the top of the overlay. At the current time HAPI requires the user to be familiar with Python, although most of the functions are prewritten and with the help of the manual one does not need to have advanced knowledge of that computer language. In order to extend the range of users, we plan to create a flexible graphical user interface (GUI). This interface will give the user a possibility to simulate, plot and compare line-by-line and raw spectral data with a flexible control of scale, units, and computational parameters (just as is possible in the current Python version of HAPI).
Total internal partition sums (TIPS) Total internal partition sums (TIPS) were determined for all molecules and isotopologues in HITRAN2016 and for a number of isotopologues of molecules of interest in planetary atmospheres. The current TIPS data are calculated in one-degree steps from 1 K to T max , where T max is determined separately for each isotopologue based on convergence of the partition sums. The TIPS are comprised of updated calculations and values from previous studies of TIPS  [112, [637] [638] [639]. The updates can be grouped into several categories: improvements in ab initio calculations that allow direct sums over energy levels, improved Q vib values using the anharmonic approximation  [640]  , and calculations for new molecule/isotopologues in the HITRAN database. The updates that were made for isotopologues in this edition of HITRAN are listed in Table  13.