The Fornax cluster provides a uniquely compact laboratory to study the detailed history of early-type galaxies and the role played by environment in driving their evolution and their transformation from late-type galaxies. Using the superb capabilities of the Multi Unit Spectroscopic Explorer on the Very Large Telescope, high-quality integral-field spectroscopic data were obtained for the inner regions of all the bright (m B ≤ 15) galaxies within the virial radius of Fornax. The stellar haloes of early-type galaxies are also covered out to about four effective radii. State-of-the-art stellar dynamical and population modelling allows to aim in particular at better characterising the disc components of fast-rotating early-type galaxies, constraining radial variations in the stellar initial-mass functions and measuring the stellar age, metallicity, and α-element abundance of stellar haloes in cluster galaxies. This paper describes the sample selection, observations, and overall goals of the survey, and provides initial results based on the spectroscopic data, including the detailed characterisation of stellar kinematics and populations to large radii; decomposition of galaxy components directly via their orbital structure; the ability to identify globular clusters and planetary nebulae, and derivation of high-quality emission-line diagnostics in the presence of complex ionised gas.

In this letter we describe how we use stellar dynamics information to constrain the shape of the stellar IMF in a sample of 27 early-type galaxies from the CALIFA survey. We obtain dynamical and stellar mass-to-light ratios, Υ dyn and Υ * , over a homogenous aperture of 0.5 R e . We use the constraint Υ dyn ≥Υ * to test two IMF shapes within the framework of the extended MILES stellar population models. We rule out a single power law IMF shape for 75% of the galaxies in our sample. Conversely, we find that a double power law IMF shape with a varying high-mass end slope is compatible (within 1σ) with 95% of the galaxies. We also show that dynamical and stellar IMF mismatch factors give consistent results for the systematic variation of the IMF in these galaxies.

We study the dynamics of the giant elliptical galaxy M87 from the central to the outermost regions with the made-to-measure (M2M) method. We use a new catalogue of 922 globular cluster line-ofsight velocities extending to a projected radius of 180 kpc (equivalent to 25 M87 effective radii), and SAURON integral field unit data within the central 2.4 kpc. 263 globular clusters, mainly located beyond 40 kpc, are newly observed by the Next Generation Virgo Survey (NGVS). For the M2M modelling, the gravitational potential is taken as a combination of a luminous matter potential with a constant stellar mass-to-light ratio and a dark matter potential modelled as a logarithmic potential. Our best fit dynamical model returns a stellar mass-to-light ratio in the I band of M/L I = 6.0 ± 0.3 M /L with a dark matter potential scale velocity of 591 ± 50 km s −1 and scale radius of 42 ± 10 kpc. We determine the total mass of M87 within 180 kpc to be (1.5 ± 0.2) × 10 13 M . The mass within 40 kpc is smaller than previous estimates determined using globular cluster kinematics that did not extend beyond ∼ 45 kpc. With our new globular cluster velocities at much larger radii, we see that globular clusters around 40 kpc show an anomalously large velocity dispersion which affected previous results. The mass we derive is in good agreement with that inferred from ROSAT X-ray observation out to 180 kpc. Within 30 kpc our mass is also consistent with that inferred from Chandra and XMM-Newton X-ray observations, while within 120 kpc it is about 20% smaller. The model velocity dispersion anisotropy β parameter for the globular clusters in M87 is small, varying from −0.2 at the centre to 0.2 at ∼ 40 kpc, and gradually decreasing to zero at ∼ 120 kpc.

We present a combination of the Schwarzschild orbit-superposition dynamical modelling technique with the spatially-resolved mean stellar age and metallicity maps to uncover the formation history of galaxies. We apply this new approach to a remarkable 5-pointing mosaic of VLT/MUSE observations obtained by Guérou et al. (2016) extending to a maximum galactocentric distance of ∼ 120 (5.6 kpc) along the major axis, corresponding to ∼ 2.5 R e . Our method first identifies 'families' of orbits from the dynamical model that represent dynamicallydistinct structures of the galaxy. Individual ages and metallicities of these components are then fit for using the stellar-population information. Our results highlight components of the galaxy that are distinct in the combined stellar dynamics/populations space, which implies distinct formation paths. We find evidence for a dynamically-cold, metal-rich disk, consistent with a gradual in-situ formation. This disk is embedded in a generally-old population of stars, with kinematics ranging from dispersion-dominated in the centre to an old, diffuse, metal-poor stellar halo at the extremities. We find also a direct correlation between the dominant dynamical support of these components, and their associated age, akin to the relation observed in the Milky Way. This approach not only provides a powerful model for inferring the formation history of external galaxies, but also paves the way to a complete population-dynamical model.

A calibration is made for the correlation between the X-ray Variability Amplitude (XVA) and black hole (BH) mass. The correlation for 21 reverberationmapped Active Galactic Nuclei (AGNs) appears very tight, with an intrinsic dispersion of 0.20 dex. The intrinsic dispersion of 0.27 dex can be obtained if BH masses are estimated from the stellar velocity dispersions. We further test the uncertainties of mass estimates from XVAs for objects which have been observed multiple times with good enough data quality. The results show that the XVAs derived from multiple observations change by a factor of 3. This means that BH mass uncertainty from a single observation is slightly worse than either reverberation-mapping or stellar velocity dispersion measurements; however BH mass estimates with X-ray data only can be more accurate if the mean XVA value from more observations is used. With this calibrated relation, the BH mass and accretion rate may be determined for a large sample of AGNs with the planned International X-ray Observatory mission.Proper interpretation of the first AGN X-ray quasi-periodic oscillation (QPO), seen in the Seyfert galaxy RE J1034+396, depends on its BH mass, which is not currently known very well. Applying this relation, the BH mass of RE J1034+396 is found to be 4 +3 −2 × 10 6 M ⊙ . The high end of the mass range follows the relationship between the 2f 0 frequencies of high-frequency QPO and the BH masses derived from the Galactic X-ray binaries.We also calculate the high-frequency constant C = 2.37 M ⊙ Hz −1 from 21 reverberation-mapped AGNs. As suggested by Gierliński et al.,where C M is the high-frequency variability derived from XVA. Given the similar shape of power-law dominated X-ray spectra in ultra-luminous X-ray sources (ULXs) and AGNs, this can be applied to BH mass estimates of ULXs. We discuss the observed QPO frequencies and BH mass estimates in the ULXs M82 X-1 and NGC 5408 X-1 and favor ULXs as intermediate mass BH systems.