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The Ritz program is a user-interactive software package that simulates and enables the assignment of spectra of asymmetric top molecules, up to high rotational quantum numbers. The set of initial assignments can be extended using generated predictions for line positions. The graphical interface of the program handles wide spectral features corresponding to overlapped lines by fitting the expected number of profiles to the experimental contour. Features of the program allow for the detection and examination of Coriolis interactions. Initially designed to work for methanol and its isotopologues, the program has been modified to assign the spectra of cyanamide, hydrazine, acetaldehyde, and oxetane. An extension of the program, LaseRitz, has been developed for the assignment and prediction of optically pumped far-infrared laser transitions. Our paper presents a description of how the Ritz program works and provides an overview of studies carried-out using this software. Key words: Ritz algorithm, absorption spectra, high resolution spectra, Fourier transform spectra, methanol, hydrazine, oxetane, far-infrared laser lines, cyanamide, acetaldehyde. Le programme Ritz est un ensemble logiciel qui simule et assigne les spectres de molecules possedant une geometrie de toupie asymetrique, allant jusqu'aux nombres quantiques eleves. L'ensemble des assignations initiales peut etre etendu en utilisant les predictioins generees pour la position des raies. L'interface graphique du programme gere un large domaine de caracteristiques correspondant a la superposition de raies, en utilisant un ajustement numerique du nombre de profils attendus au contour experimental. Le programme permet la detection et l'examen des effets de Coriolis. Initialement ecrit pour le methanol et ses isotopologues, le programme a plus tard ete modifie pour identifier les spectres de cyanamide, d'hydrazine, d'acetaldehyde et d'oxetane. LaserRitz est une extension du programme, qui a ete developpee pour l'assignation et la prediction des transitions optiquement pompees par laser dans l'infrarouge lointain. Nous decrivons ici comment fonctionne le programme et fournissons un survol des recherches qui peuvent etre completees en utilisant ce programme. [Traduit par la Redaction] Mots-cles : algorithme de Ritz, spectre d'absorption, spectres de haute resolution, spectres a transformee de Fourier, methanol, hydrazine, oxetane, raies laser dans l'infrarouge lointain, cyanamide, acetaldehyde., Introduction The advancement of spectroscopic techniques and associated theoretical studies during the second half of the twentieth century has enabled scientists to explore the crowded spectra of many multi-atom molecules, [...]

This paper discusses recent approaches to gender-inclusive mentoring and leadership at different stages of one's professional life. We will discuss life scenarios where mentoring makes a difference, different types of mentoring, how to find a mentor, roles and expectations of mentors and mentees, mentoring events, and challenges in the mentoring process. We will outline the importance of leadership activities in the professional development of young professionals. Traits of good leaders, leadership strategies, and lessons learned from good leadership examples, will be presented. Last, we will discuss different ways of defining and achieving success in professional life and beyond. Key words: mentoring, education, physics education research, teaching strategies, leadership, training, sensitivity training, success, diversity. Nous discutons ici de recentes approches de mentorat et de leadership a differentes etapes d'une vie professionnelle, en tenant compte des sexes. Nous examinerons des scenarios de vie ou le mentorat fait une difference, differents types de mentorat, comment trouver un mentor, des roles et des attentes des mentors et des mentores, d'activites de mentorat et des defis dans le processus de mentorat. Nous soulignerons l'importance des activites de leadership dans le developpement professionnel des jeunes professionnels. Nous presenterons les caracteristiques des bons leaders, les strategies de leadership et les lecons apprises d'exemples de bon leadership. Finalement, differentes facons seront examinees pour definir et atteindre le succes dans la vie professionnelle et au-dela. [Traduit par la Redaction] Mots-cles : mentorat, leadership, diversite, inclusion, succes., 1. Introduction During the past two decades, efforts have been made in many countries to nurture the interest in science of young girls [1-4], to encourage the participation of female [...]

We report measurement results for line positions, intensities, half-width, and pressure-induced shift coefficients and line mixing coefficients for [N.sub.2]O broadened by air in the [v.sub.3] band. The high signal-to-noise ratio spectra have been recorded at high resolution using the McMath-Pierce Fourier transform spectrometer formerly located at the National Solar Observatory on Kitt Peak, Ariz., USA. The spectra were analyzed using a multispectrum nonlinear least-squares curve-fitting technique employing the speed-dependent Voigt profile with a Rosenkranz (weak) line mixing component. The speed dependence parameters were calculated as suggested in the study of Kochanov (J. Quant. Spectrosc. Radiat. Transf. 189, 18 (2017). doi:10.1016/j.jqsrt.2016.11.007). Several comparisons have been performed between the retrieved parameters and previously published results. For [absolute value of (m)] [less than or equal to] 40, our results for line positions, broadening, and line mixing coefficients agree best with the results of Loos et al. (J. Quant. Spectrosc. Radiat. Transf. 151, 300 (2015). doi:10.1016/j.jqsrt.2014.10.008). Also, we compared the obtained line positions and intensities with the corresponding values in HITRAN2016 and GEISA-2015 databases. No significant or systematic differences were noticed. The precision of our line positions was estimated to be 3 x [10.sup.-5] [cm.sup.-1]. The reported line positions, intensities, and air-broadening coefficients are accurate to better than 2%. The accuracy of air-pressure- induced line shifts and line mixing coefficients is better than 5%. The line mixing coefficients and air-broadening coefficients were also calculated using the exponential power gap scaling law, and these calculated values were found to be in good agreement with the experimental results. Key words: [N.sub.2]O, air-broadening, positions, intensities, pressure-induced shift, line mixing coefficients, multispectrum nonlinear fit. Nous presentons des resultats pour les positions des raies, leur intensite et leur largeur a mi-hauteur et les coefficients du deplacement induit par la pression et les coefficients de melange des raies du [N.sub.2]O elargies par l'air dans la bande [v.sub.3]. Les spectres de haut rapport signal sur bruit sont enregistres a haute resolution a l'aide du spectrometre a transformee de Fourier McMath-Pierce anterieurement installe a l'Observatoire Solaire National de Kitt Peak, Ariz., USA. Les spectres sont analyses en utilisant une technique d'ajustement par moindres carres non lineaire multi- spectrale qui emploie un profile de Voigt dependant de la vitesse avec composante de melange de raies (faible) de Rosenkranz. Les parametres dependants de la vitesse sont calcules suivant la suggestion de l'etude de Kochanov (J. Quant. Spectrosc. Radiat. Transf. 189, 18 (2017). doi:10.1016/j.jqsrt.2016.11.007). Plusieurs comparaisons sont faites entre les parametres que nous obtenons et d'autres valeurs deja dans la litterature. Pour [absolute value of (m)] [less than or equal to] 40, nos resultats pour les positions des raies, les coefficients d'elargissement et de melange de raies agreent mieux avec les resultats de Loos et al. J. Quant. Spectrosc. Radiat. Transf. 151, 300 (2015). doi:10.1016/j.jqsrt.2014.10.008). Nous comparons aussi les positions des raies et leurs intensites avec les bases de donnees HITRAN2016 et GEISA-2015. Nous ne notons aucune difference, significative ou systematique. Nous estimons la precision de position des raies a 3 x [10.sup.-5] [cm.sup.-1]. Les positions des raies, les intensites et les coefficients d'elargissement du a l'air ont une precision meilleure que 2%. La precision sur les deplacements des raies induits par la pression de l'air et celle sur les coefficients de melange de raies sont a l'interieur de 5%. Nous calculons aussi les coefficients de melange et ceux d'elargissement du a l'air a l'aide de la loi d'echelle EPG et ces valeurs sont en bon accord avec les valeurs experimentales. [Traduit par la Redaction] Mots-cles : [N.sup.2]O, elargissement du a l'air, intensites, deplacement induit par pression, coefficients de melange de raies., 1. Introduction It is well documented that gases included in the [N.sub.x][O.sub.y] family (NO, N[O.sub.2], [N.sub.2][0.sub.2], [N.sub.2]0, etc.) play a crucial role in terrestrial atmospheric chemistry. For example, these gases [...]

Caption: Professor Li-Hong Xu. ? 2019 Chinese Cultural Association of Saint John Guest Editor Adriana [...]

This special issue of the Canadian Journal of Physics is dedicated to Professor Li-Hong Xu (May 2,1957-January 21, 2019) in recognition of her remarkable contributions to molecular spectroscopy, teaching, and [...]

The spectral line parameters of carbon dioxide have been measured in the laser band I (00011 ← 10001) centred at 10.4 µm. The spectra were recorded at room temperature using the spectroscopic instrumentation at the far- infrared beamline, Canadian Light Source, Saskatoon, Sask. The spectral line intensities, air- and self- broadened Lorentz half widths, and pressureinduced shift coefficients were retrieved for 48 spectral lines using a multispectrum fit technique (Benner et al. J. Quant. Spectrosc. Radiat. Transfer, 53,705 (1995)). Line parameters were retrieved using the Voigt and speed-dependent Voigt models. The deviations between our results and other results reported in the literature and in the HITRAN08 (Rothman et al. J. Quant. Spectrosc. Radiat. Transfer, 110, 533 (2009)) database were examined and discussed. The effect of errors in fitting channel spectra parameters was examined and found to be mitigated by the inclusion of channels in the multispectral fit. PACS Nos.: 33.20.-t, 33.20.Ea, 33.70.Jg, 32.70.Jz. Nous avons mesure les parametres des raies du dioxyde de carbone dans la bande laser I (00011←10001) centree a 10.4 µm. Nous avons enregistre les spectres a la temperature de la piece en utilisant l'instrumentation spectroscopique de la ligne d'infrarouge lointain du Centre Canadien de Rayonnement a Saskatoon, Sask. Une technique multi-spectrale (Benner et al. J. Quant. Spectrosc. Radiat. Transfer, 53,705 (1995)) d'ajustement numerique nous a permis de retrouver pour 48 raies spectrales, les intensites des raies, les demi-largeurs de Lorentz auto ou air elargies et les coefficients de deplacement induit par la pression. Les parametres de raie ont ete obtenus en utilisant les modeles de Voigt et de Voigt dependant de la vitesse. Nous avons examine et discute les deviations entre nos resultats et ceux apparaissant dans la litterature et dans la base de donnees HITRAN08 (Rothman et al. J. Quant. Spectrosc. Radiat. Transfer, 110, 533 (2009)). L'effet des erreurs dans l'ajustement numerique des parametres de spectre a ete etudie et nous trouvons qu'il est attenue par l'ajustement multi-spectral. [Traduit par la Redaction], 1. Introduction Increasing efforts to monitor the atmospheric composition aim to understand the atmospheric system and its changes, such as the increase of greenhouse gases, loss of stratospheric ozone, poor [...]

Recently, the high radiance of synchrotron sources has been used to enhance FTIR spectrometer performance. However, excessive channel spectra when synchrotron sources are used degrade the quality of retrieved spectral parameters. We have investigated seven different techniques for handling channel spectra. These techniques were used to reduce channel spectra for a test group of seven samples of C[O.sub.2] mixed with air recorded using the synchrotron source at the Canadian Light Source. The increases in signal to noise ratio (SNR) of spectra handled with each technique were calculated. SNR results showed that transmission spectra, produced using synthetic background spectra with simulated channel spectra, achieved the highest SNR improvement. However, when the spectra groups were fitted using a nonlinear least square fit algorithm, the technique using channel spectra fitting produced the smallest fitting residual. Moreover, the retrieved intensities and air broadening coefficients of 21 spectral lines showed that the spectral fitting technique produced the most accurate values as compared to the HITRAN 2008 database (Rothman et al. J. Quant. Spectrosc. Radiat. Transfer, 110, 533 (2009)). Although the spectral fitting technique was accurate in retrieving spectral line parameters, applying the technique at wider spectral ranges reduced this accuracy. PACS Nos.: 33.20.-t, 33.20.Ea, 33.70.Jg, 32.70.Jz. Recemment, la haute luminance des sources synchrotron a ete utilisee pour augmenter la performance des spectrometres FTIR. Cependant, l'exces de spectres canneles, lorsque des sources synchrotron sont utilisees, degrade la qualite des parametres spectraux recuperes. Nous avons etudie sept techniques differentes pour gerer les spectres canneles. Ces techniques ont ete utilisees pour reduire les spectres canneles dans une serie de tests impliquant sept echantillons de C[O.sub.2] melange a de l'air, enregistres au Centre Canadien de Radiation Synchrotron. Nous avons calcule l'amelioration du rapport signal sur bruit (SNR) pour chaque technique. Les resultats SNR montrent que les spectres de transmission, produits en utilisant des spectres de fond (background) avec des spectres canneles simules, montrent la meilleure amelioration SNR. Cependant, lorsque nous faisons un lissage des groupes de spectres en utilisant un algorithme non lineaire de moindres carres, la technique qui utilise le lissage des spectres canneles a produit le plus petit residu de lissage. De plus, les intensites mesurees et les elargissements de raie dues a l'air de 21 raies spectrales montrent que la technique de lissage des spectres canneles produit les valeurs les plus precises lorsque comparees a la base de donnees HITRAN 2008 (Rothman et al. J. Quant. Spectrosc. Radiat. Transfer, 110,533 (2009)). Meme si le lissage des spectres canneles est precis dans la recuperation des parametres des raies spectrales, son application a des domaines spectraux plus larges reduit cette precision. [Traduit par la Redaction], 1. Introduction In spite of all its advantages, there is one major drawback that can make the signal to noise ratio (SNR) of recorded Fourier transform spectra decline, namely the [...]

Six nitrogen-perturbed transitions of acetylene within the [v.sub.1] + [v.sub.3] absorption band have been recorded using a three-channel diode laser spectrometer. The goal being an improved understanding of both broadening and narrowing effects of low-pressure acetylene under the influence of nitrogen gas. To this end we have examined [C.sub.2][H.sub.2] spectra using a hard collision Rautian profile over a range of five temperatures (213-333 K) and five pressures (5-40 Torr). From these fits we have obtained the [N.sub.2]-broadening and narrowing coefficients of [C.sub.2][H.sub.2] and examined their temperature dependence. The experimentally measured narrowing coefficients have been used to estimate the nitrogen diffusion coefficients ([D.sub.12]) and are presented within. The broadening coefficients and corresponding temperature dependence exponents have also been compared to that of calculations completed using a classical impact approach on an ab initio potential energy surface. We have observed good agreement between our theoretical and experimental results. PACS Nos.: 33.20.-t, 33.20.Ea, 33.70.Jg, 32.70.Jz. Utilisant un spectrometre a diode laser a trois canaux, nous avons enregistre six transitions dans l'acetylene perturbee par de l'azote a l'interieur de la bande d'absorption [v.sub.1] + [v.sub.3]. Le but est d'ameliorer notre comprehension des mecanismes d'elargissement et de resserrement dans l'acetylene a basse pression en presence d'azote. A cette fin, nous avons etudie les spectres de [C.sub.2][H.sub.2] en utilisant un profil de Rautian de collisions dures pour cinq temperatures dans le domaine 213-333 K et cinq pressions dans le domaine 5-40 Torr. A partir ce ces ajustements numeriques, nous avons obtenu les coefficients d'elargissement et de resserrement de [C.sub.2][H.sub.2] et avons examine leur dependance en temperature. Nous avons utilise les valeurs obtenues experimentalement pour les coefficients de resserrement afin d'estimer les coefficients de diffusion de l'azote ([D.sub.12]) et nous les presentons ici. Les coefficients d'elargissement et la dependance en temperature sont aussi compares aux resultats de calculs qui utilisent une approche de collisions classiques et une surface d'energie potentielle obtenue de principes premiers. Nous observons un bon accord entre calculs theoriques et valeurs experimentales. [Traduit par la Redaction], 1. Introduction Accurate detailed knowledge of individual line parameters of the spectrum of acetylene is critical for the correct interpretation and modeling of many planetary atmospheres containing hydrocarbon molecules. The [...]

We present a line shape analysis of the P(2) and P(7) transitions of CO broadened by Xe in the fundamental band. The spectra were recorded at 349 K using a difference frequency laser spectrometer. To obtain information on the influence of Dicke narrowing, relaxation speed dependence, and line mixing effects, several models for implementation of Dicke narrowing and (or) speed-dependent effects are discussed. From experimental data analysis, we conclude that line shape models taking into account the Dicke effect only fail in the high pressure regime and lead to optical diffusion parameters that are much larger than the kinetic diffusion ones. On the contrary, a fair interpretation of data is obtained from speed-dependent models, so that it is possible to derive a quantitative estimate of optical diffusion effects that appear much smaller than the kinetic diffusion ones. Xe-broadening coefficients of CO lines in the fundamental band at 297 and 349 K are calculated from a semi-classical formalism involving successively two intermolecular potentials, the atom-atom Lennard-Jones model, and a three-term expansion of Legendre polynomials with four adjustable parameters. PACS Nos: 32.70.Jz, 33.70.Jg, 33.20.Ea Nous presentons une etude des profils de raie des transitions P(2) et P(7) de la bande fondamentale de la molecule de CO, elargies par du Xenon. Les spectres ont ete enregistres a 349 K en utilisant un spectrometre a difference de frequences. Pour obtenir de l'information sur le retrecissement induit par les collisions (effet Dicke), la dependance en vitesse de la relaxation et les effets d'interferences entre raies, nous analysons plusieurs modeles qui tiennent compte de l'effet Dicke et de la dependance en vitesse. De l'analyse des donnees experimentales, nous concluons que les modeles de profils de raie qui prennent en compte le retrecissement Dicke ne deviennent inapplicables a hautes pressions et donnent des parametres de diffusion optique beaucoup plus grands que ceux de diffusion cinetique. D'un autre cote, les modeles comprenant la dependance en vitesse donnent une interpretation raisonnable des donnees experimentales et il est ainsi possible d'obtenir une evaluation quantitative des effets de diffusion optique qui apparaissent ici beaucoup plus petits que ceux de diffusion cinetique. Les coefficients d'elargissement des raies du CO par le Xenon dans la bande fondamentale a 297 et 349 K sont evalues grace a un formalisme semi-classique qui utilise successivement deux potentiels intermoleculaires, le modele atome-atome de Lennard-Jones et un developpement a trois termes en polynomes de Legendre avec quatre parametres ajustables., 1. Introduction There is a need in atmospheric research to accurately model absorption profiles over a wide range of pressures and temperatures. Using a correct understanding of the physics of [...]

Abstract: In this study, we report the first experimental measurements of air-broadening and air-induced pressure-shift coefficients for approximately 378 transitions in the [v.sub.2] fundamental band of C[H.sub.3]D. These results were [...]

Ursula Franklin (1921-2016), a pioneer archaeometrist at the University of Toronto, was recognized in Canada as a stellar scientist, and an activist for the cause of science, peace, and feminism. [...]

Physics has traditionally been an area dominated by men, with fewer opportunities for women to excel, irrespective of their location in East or West. This may be partly because of [...]