The lopsided spiral galaxy NGC1637 with SITELLE

Étienne Massé ( Université Laval )

Using the imaging spectrograph SITELLE at the CFHT, a thorough analysis of the isolated lopsided spiral galaxy NGC 1637 was performed with the goal to find new clues about the origin of its asymmetry. Four filters have been used (SN1 which includes [OII]3727, SN2 with Hb and [OIII]4959, 5007, C3 with Mgb and Fe absorption lines between x and y A, and SN3 with Ha, [NII]6… and [SII]6717,6731). Maps of the strong emission lines have been obtained revealing more than 700 HII regions. Spectra of the old stellar populations underneath these emission regions have been modeled using the code PpXF. An analysis of the contribution of C3 to the fit was performed. Corrected emission line ratios are used to study the HII regions properties over the whole galaxy and to obtain a catalogue of HII regions. A dynamic analysis revealed that the kinematic and luminosity centers are separated by close to 200 pc.