The intricate link between galaxy dynamics and intrinsic shape (or why so-called prolate rotation is a misnomer)

AbstractMany recent integral field spectroscopy (IFS) survey teams have used stellar kinematic maps combined with imaging to statistically infer the underlying distributions of galaxy intrinsic shapes. With now several IFS samples at our disposal, the method, which was originally proposed by M. Franx and collaborators in 1991, is gaining in popularity, having been so far applied to ATLAS3D, SAMI, MANGA and MASSIVE. We present results showing that a commonly assumed relationship between dynamical and intrinsic shape alignment does not hold in Illustris, affecting our ability to recover accurate intrinsic shape distributions. A further implication is that so-called “prolate rotation”, where the bulk of stars in prolate galaxies are thought to rotate around the projected major axis, is a misnomer.

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The delay time distribution of supernovae from integral-field spectroscopy of nearby galaxies

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/staa3876 ◽

2020 ◽

Author(s):

Asier Castrillo ◽

Yago Ascasibar ◽

Lluís Galbany ◽

Sebastián F Sánchez ◽

Carles Badenes ◽

...

Keyword(s):

Delay Time ◽

Time Distribution ◽

Host Galaxies ◽

Galaxy Dynamics ◽

Chemical Enrichment ◽

Integral Field Spectroscopy ◽

Field Spectroscopy ◽

Nearby Galaxies ◽

Integral Field ◽

Shed Light

Abstract Constraining the delay-time distribution (DTD) of different supernova (SN) types can shed light on the timescales of galaxy chemical enrichment and feedback processes affecting galaxy dynamics, and SN progenitor properties. Here, we present an approach to recover SN DTDs based on integral field spectroscopy (IFS) of their host galaxies. Using a statistical analysis of a sample of 116 supernovae in 102 galaxies, we evaluate different DTD models for SN types Ia (73), II (28) and Ib/c (15). We find the best SN Ia DTD fit to be a power law with an exponent α = −1.1 ± 0.3 (50% confidence interval), and a time delay (between star formation and the first SNe) $\Delta = 50^{+100}_{-35}~Myr$ (50% C.I.). For core collapse (CC) SNe, both of the Zapartas et al. (2017) DTD models for single and binary stellar evolution are consistent with our results. For SNe II and Ib/c, we find a correlation with a Gaussian DTD model with $\sigma = 82^{+129}_{-23}~Myr$ and $\sigma = 56^{+141}_{-9}~Myr$ (50% C.I.) respectively. This analysis demonstrates that integral field spectroscopy opens a new way of studying SN DTD models in the local universe.

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The stellar structure of early-type galaxies: a wide-field Mitchell Spectrograph view

Proceedings of the International Astronomical Union ◽

10.1017/s174392131601108x ◽

2016 ◽

Vol 11 (S321) ◽

pp. 288-288

Author(s):

N. F. Boardman ◽

A. Weijmans ◽

R. C. E. van den Bosch ◽

L. Zhu ◽

A. Yildirim ◽

...

Keyword(s):

Effective Radius ◽

Stellar Structure ◽

Wide Field ◽

Early Type ◽

Integral Field Spectroscopy ◽

Field Spectroscopy ◽

Integral Field ◽

Made In

Much progress has been made in recent years towards understanding how early-type galaxies (ETGs) form and evolve. SAURON (Bacon et al. 2001) integral-field spectroscopy from the ATLAS3D survey (Cappellari et al. 2011) has suggested that less massive ETGs are linked directly to spirals, whereas the most massive objects appear to form from a series of merging and accretion events (Cappellari et al. 2013). However, the ATLAS3D data typically only extends to about one half-light radius (or effective radius, Re), making it unclear if this picture is truly complete.

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