Nearby galaxies

Our group works to make some light in different topics which are listed bellow

  • Stellar popullations and galaxy dynamics with MEGARA
  • A fast-rotating disky bulge in NGC 7025
  • 2D spectroscopy of M32 with MEGARA
  • Neutral and Ionized winds in Nearby Galaxies with MEGARA
  • Study of multiple neutral and ionized-gas kinematic components with MEGARA

Stellar popullations and galaxy dynamics with MEGARA

Mario Chamorro- Cazorla & MEGARA Consortium & commissioning team

Test Case NGC 7025: Our long-term objective is to target a well-defined sample of 150 nearby disks from the S4G survey to measure their 2D

(1) stellar velocity ellipsoids,

(2) stellar population ages and

(3) abundances using MEGARA IFU spectroscopy in the CaT region at R=20k and in multiple R=6k setups.

Test Case: SSP models. Mock spectra from individual SSPs are computed (Sánchez-Blázquez et al. 2006; Vazdekis et al. 2010) with different ages and Solar metallicity. Each SSP is broadened to different velocity dispersions and added different noise levels. pPXF method (Cappellari, 2017, MNRAS, 466, 798) is used to derive the age and metallicity.
NGC 7025 Radial SFH (mass fractions):

The average of the weights (in mass fraction) for each of the SSP models needed by pPXF to fit the 100 resampled spectra in LR-V VPH is shown.

MEGARA Stellar kinematics in NGC7025

Dullo et al. 2019, ApJ

Results from the analysis of the stellar kinematics of the central regions of the CALIFA galaxy NGC7025 (one LCB pointing in LR-V with 45min exposure and a physical resolution of 200 pc) showing evidence for fast rotation with associated cylindrical rotation and strong anti-correlation V – h3 (e.g. Falcón-Barroso et al. 2017).

2D spectroscopy of M32 with MEGARA

Armando Gil de Paz & MEGARA Consortium & commissioning team

MEGARA allows to obtain deep 2D spectroscopy of extended objects.

M32 is the nearest (compact) elliptical and a companion of the Andromeda galaxy. It is now believed to be the remnant of a more massive system stripped of its stars.

The 2D kinematics of M32 are key to understand the effects of interactions on the formation of dwardfs, ellipticals, lenticular and to confirm M32’s true nature.

The results: Distortions (non asymmetry) of the sigma and h4 maps are testimony of a major interaction with Andromeda.

Neutral and Ionized winds in Nearby Galaxies with MEGARA

(Castillo-Morales et al 2019, in preparation)

Our aim is to study the existence, frequency and strength of winds in normal, quiescent galaxies, and how they compare to active galaxies (galaxies form CALIFA and S4G sample).

Using MEGARA (LCB/IFU mode) we can simultaneously study multiple phases of the outflows across the innermost regions of nearby galaxies at sub-kpc scales.

Study of multiple neutral and ionized-gas kinematic components with MEGARA

Cristina Catalán-Torrecilla & MEGARA Consortium & commissioning team

Despite its complex kinematics, MEGARA data alone have allowed providing a complete interpretation for the stellar, ionized gas and neutral gas distribution and dynamics in the inner regions of S0/a galaxy UGC10205 that provides further evidence for the variety of mechanisms that can shape the current-day properties of lenticular galaxies.