What's New
Oct 14, 2009
Sorting of My Spectra
Organizing your spectra is even easier now, with the new sorting utility. Clicking on any heading (Name, Lower Limit, Upper Limit, Points, Type, Date) in the My Spectra tool will sort all your spectra by that parameter. Clicking again will reverse-sort by that parameter.
Oct 1, 2009
Average Values
The average value is computed and printed on every plot created with the My Spectra tools. This includes plots with user-specified spectral ranges, difference plots, and plots of products or sums. Difference plots now include both the average and RMS difference, computed only within the plotted spectral range. [Example]
Sept 23, 2009
Difference-order on My Spectra
Users can now specify the order in which difference spectra are computed. This allows users to maintain consistency when collecting and comparing many different plots from various spectra saved in their My Spectra tool.
Sept 18, 2009
HITRAN update for C2H6 (ethane)
Line parameters for a second ethane isotopologue, (13)C(12)CH6, have been added to the HITRAN2008 database. The new data have been uploaded, and all calculations using HITRAN 2008 from now on will be made with these new line parameters. [Example] [More details]
Aug 11, 2009
Save Atmospheric Path Setups
Users can now save the settings of any atmospheric path calculation. Similar to the Gas Cell Calculator, all parameters are stored in the My Settings tab on the Atmospheric Paths tool. This allows you to recall and repeat calculations without having to retype the information, and provides an excellent for record-keeping.
Aug 5, 2009
Dots-only Plots on Linelist Browser
We added another plot option for graphing the line intensities in the Linelist Browser: dots without sticks. Previously, the only options were to plot the intensities as plain sticks or as sticks with dots. Now we've added a third option, dots without sticks [Example].
July 23, 2009
OCS line parameter update
Updated OCS line parameters from HITRAN have been released. Broadening parameters and line intensities of all OCS isotopologues are affected. The new data have been uploaded, and all calculations using HITRAN 2008 from now on will be made with these new line parameters. [Example plot] [More details]
July 2, 2009
Update to HITRAN 2008 H2O
The HITRAN committee has released an update to the water vapor line parameters. This update affects the line intensities of the HDO water vapor isotopologue at wavenumbers above 11,500 cm-1. The new line parameters have been ingested into our database, and all calculations using HITRAN 2008 from now on will be made with these new line parameters. [Example plot] [More details]
June 29, 2009
New website design
We've completely overhauled the look-and-feel of the website. With the addition of so many spectral modeling tools, the existing layout was becoming too complicated for new users. We created a new top-level design to make transition between the various tools faster, easier and more intuitive. The underlying calculations are unchanged, and accurate results are still our number one priority.
June 12, 2009
Continua Models for N2, O2 and H2O
Continuum absorption/emission effects for N2, O2 and H2O are now automatically included as needed for all Gas Cell and Atmospheric Path simulations. These continuum models augment the standard “line-by-line” calculation, more accurately accounting for far-wing effects at high pressures.
For O2 and N2, the spectral ranges affected are 1345-1820 cm-1 and 2105-2620 cm-1, respectively. The H2O continuum is significant at wavenumbers below 600 cm-1 and between 1200 and 2000 cm-1. For all three gases, the effect is proportional to pressure, and is negligible at pressures less than ~10 mbar.
Spectra for these gases in these spectral ranges calculated prior to this update did not include continuum effects, and should be recalculated with the new version. [more details]
May 25, 2009
HITRAN 2008 data released
The 2008 edition of the HITRAN data were released this earlier this month, and these data are now available on spectralcalc.com for download, display and for use in spectral simulations. The HITRAN 2004 data will remain available indefinitely, and will be the default for public use, but we recommend using the new HITRAN 2008 data wherever possible.
To assess the impact of the new data on your earlier results, you can easily compare the datasets using the Line List Browser or by simulating spectra with each, saving them, and using the My Spectra tool to view the residual difference.
Apr 22, 2009
Major Update to Website
We've completely updated our website, and added several important new capabilities. Highlights include:
Atmospheric Paths
With the "Atmospheric Path" tool, you can now simulate accurate molecular transmittance and/or emission spectra for paths through the Earth's atmosphere. Begin by choosing from a list of model atmospheres and, if needed, tailor the concentrations of absorbing gases to your specific application. As of now, both horizontal and vertical paths are supported, and developers are putting the finishing touches on the more general slant-path geometries. These are the same models used by NASA and Universities worldwide in space-based atmospheric science missions.
My Spectra Tool
Subscribers now have the option of saving spectra from any of their calculations, or uploading their own spectra, whether lab, field or model based. Spectra can be compared, multiplied (transmittance) or summed (radiance). Plots of the residual differences between two spectra can help you quickly isolate regions of interest. Interpolation and resampling are handled quickly and efficiently behind the scenes, so the user doesn't have to contend with these time-consuming tasks. This is an invaluable tool for spectroscopic research.
Group Account Tools
Group subscriptions can now be purchased online and administered instantly, without any need for email or phone support. Administrators can manage their group account from the "My Account" link. Here you will see a list of all users currently in the group. You can add or delete users, and can designate an additional administrator if desired. Users can also join the group by logging in and entering the group code in "My Account".
Oct 14, 2009
Sorting of My Spectra
Organizing your spectra is even easier now, with the new sorting utility. Clicking on any heading (Name, Lower Limit, Upper Limit, Points, Type, Date) in the My Spectra tool will sort all your spectra by that parameter. Clicking again will reverse-sort by that parameter.
Oct 1, 2009
Average Values
The average value is computed and printed on every plot created with the My Spectra tools. This includes plots with user-specified spectral ranges, difference plots, and plots of products or sums. Difference plots now include both the average and RMS difference, computed only within the plotted spectral range. [Example]
Sept 23, 2009
Difference-order on My Spectra
Users can now specify the order in which difference spectra are computed. This allows users to maintain consistency when collecting and comparing many different plots from various spectra saved in their My Spectra tool.
Sept 18, 2009
HITRAN update for C2H6 (ethane)
Line parameters for a second ethane isotopologue, (13)C(12)CH6, have been added to the HITRAN2008 database. The new data have been uploaded, and all calculations using HITRAN 2008 from now on will be made with these new line parameters. [Example] [More details]
Aug 11, 2009
Save Atmospheric Path Setups
Users can now save the settings of any atmospheric path calculation. Similar to the Gas Cell Calculator, all parameters are stored in the My Settings tab on the Atmospheric Paths tool. This allows you to recall and repeat calculations without having to retype the information, and provides an excellent for record-keeping.
Aug 5, 2009
Dots-only Plots on Linelist Browser
We added another plot option for graphing the line intensities in the Linelist Browser: dots without sticks. Previously, the only options were to plot the intensities as plain sticks or as sticks with dots. Now we've added a third option, dots without sticks [Example].
July 23, 2009
OCS line parameter update
Updated OCS line parameters from HITRAN have been released. Broadening parameters and line intensities of all OCS isotopologues are affected. The new data have been uploaded, and all calculations using HITRAN 2008 from now on will be made with these new line parameters. [Example plot] [More details]
July 2, 2009
Update to HITRAN 2008 H2O
The HITRAN committee has released an update to the water vapor line parameters. This update affects the line intensities of the HDO water vapor isotopologue at wavenumbers above 11,500 cm-1. The new line parameters have been ingested into our database, and all calculations using HITRAN 2008 from now on will be made with these new line parameters. [Example plot] [More details]
June 29, 2009
New website design
We've completely overhauled the look-and-feel of the website. With the addition of so many spectral modeling tools, the existing layout was becoming too complicated for new users. We created a new top-level design to make transition between the various tools faster, easier and more intuitive. The underlying calculations are unchanged, and accurate results are still our number one priority.
June 12, 2009
Continua Models for N2, O2 and H2O
Continuum absorption/emission effects for N2, O2 and H2O are now automatically included as needed for all Gas Cell and Atmospheric Path simulations. These continuum models augment the standard “line-by-line” calculation, more accurately accounting for far-wing effects at high pressures.
For O2 and N2, the spectral ranges affected are 1345-1820 cm-1 and 2105-2620 cm-1, respectively. The H2O continuum is significant at wavenumbers below 600 cm-1 and between 1200 and 2000 cm-1. For all three gases, the effect is proportional to pressure, and is negligible at pressures less than ~10 mbar.
Spectra for these gases in these spectral ranges calculated prior to this update did not include continuum effects, and should be recalculated with the new version. [more details]
May 25, 2009
HITRAN 2008 data released
The 2008 edition of the HITRAN data were released this earlier this month, and these data are now available on spectralcalc.com for download, display and for use in spectral simulations. The HITRAN 2004 data will remain available indefinitely, and will be the default for public use, but we recommend using the new HITRAN 2008 data wherever possible.
To assess the impact of the new data on your earlier results, you can easily compare the datasets using the Line List Browser or by simulating spectra with each, saving them, and using the My Spectra tool to view the residual difference.
Apr 22, 2009
Major Update to Website
We've completely updated our website, and added several important new capabilities. Highlights include:
Atmospheric Paths
With the "Atmospheric Path" tool, you can now simulate accurate molecular transmittance and/or emission spectra for paths through the Earth's atmosphere. Begin by choosing from a list of model atmospheres and, if needed, tailor the concentrations of absorbing gases to your specific application. As of now, both horizontal and vertical paths are supported, and developers are putting the finishing touches on the more general slant-path geometries. These are the same models used by NASA and Universities worldwide in space-based atmospheric science missions.
My Spectra Tool
Subscribers now have the option of saving spectra from any of their calculations, or uploading their own spectra, whether lab, field or model based. Spectra can be compared, multiplied (transmittance) or summed (radiance). Plots of the residual differences between two spectra can help you quickly isolate regions of interest. Interpolation and resampling are handled quickly and efficiently behind the scenes, so the user doesn't have to contend with these time-consuming tasks. This is an invaluable tool for spectroscopic research.
Group Account Tools
Group subscriptions can now be purchased online and administered instantly, without any need for email or phone support. Administrators can manage their group account from the "My Account" link. Here you will see a list of all users currently in the group. You can add or delete users, and can designate an additional administrator if desired. Users can also join the group by logging in and entering the group code in "My Account".