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[Abridged] We present the apparent stellar angular momentum of 300 galaxies across the Hubble sequence, using integral-field spectroscopic data from the CALIFA survey. Adopting the same $\lambda_\mathrm{R}$ parameter previously used to distinguish between slow and fast rotating early-type (elliptical and lenticular) galaxies, we show that spiral galaxies as expected are almost all fast rotators. Given the extent of our data, we provide relations for $\lambda_\mathrm{R}$ measured in different apertures, including conversions to long-slit 1D apertures. Our sample displays a wide range of $\lambda_\mathrm{Re}$ values, consistent with previous IFS studies. The fastest rotators are dominated by relatively massive and highly star-forming Sb galaxies, which preferentially reside in the main star-forming sequence. These galaxies reach $\lambda_\mathrm{Re}$ values of $\sim$0.85, are the largest galaxies at a given mass, and display some of the strongest stellar population gradients. Compared to the population of S0 galaxies, our findings suggest that fading may not be the dominant mechanism transforming spirals into lenticulars. Interestingly, we find that $\lambda_\mathrm{Re}$ decreases for late-type Sc and Sd spiral galaxies, with values than in occasions puts them in the slow-rotator regime. While for some of them this can be explained by their irregular morphologies and/or face-on configurations, others are edge-on systems with no signs of significant dust obscuration. The latter are typically at the low-mass end, but this does not explain their location in the classical ($V/\sigma$,$\varepsilon$) and ($\lambda_\mathrm{Re}$,$\varepsilon$) diagrams. Our initial investigations, based on dynamical models, suggest that these are dynamically hot disks, probably influenced by the observed important fraction of dark matter within R$_\mathrm{e}$., Comment: 17 pages, 7 figures, A&A accepted

Aims. In this paper, we study the dense gas of the molecular cloud LDN 1287 (L1287), which harbors a double FU Ori system, an energetic molecular outflow, and a still-forming cluster of deeply embedded low-mass young stellar objects that show a high level of fragmentation. Methods. We present optical Hα and [SII], and VLA NH3 (1, 1) and (2, 2) observations with an angular resolution of ∼3′′.5. The observed NH3 spectra have been analyzed with the Hyperfine Structure tool, fitting simultaneously three different velocity components. Results. The NH3 emission from L1287 comes from four different structures: a core associated with RNO 1, a guitar-shaped core (the Guitar) and two interlaced filaments (the blue and red filaments) roughly centered toward the binary FU Ori system RNO 1B/1C and its associated cluster. Regarding the Guitar core, there are clear signatures of gas infall onto a central mass that has been estimated to be ∼2.1Mpdbl. Regarding the two filaments, they have radii of ∼0.03 pc, masses per unit length of ∼50Mpdbl pc-1, and are in near isothermal equilibrium. A central cavity is identified, probably related with the outflow and also revealed by the Hα and [SII] emission, with several young stellar objects near its inner walls. Both filaments show clear signs of perturbation by the high-velocity gas of the outflows driven by one or several young stellar objects of the cluster. The blue and red filaments are coherent in velocity and have nearly subsonic gas motions, except at the position of the embedded sources. Velocity gradients across the blue filament can be interpreted either as infalling material onto the filament or rotation. Velocity gradients along the filaments are interpreted as infall motions toward a gravitational well at the intersection of the two filaments. © ESO 2020., We thank Eugenio Schisano for providing us with the Herschel catalogue of the region. We thank the referee for his/her careful and helpful review of the paper. This work has been partially supported by the State Agency for Research (AEI) of the Spanish MCIU through the AYA2017-84390-C2 grant (cofunded with FEDER funds), and through the "Unit of Excellence Maria de Maeztu 2020-2023" award to the Institute of Cosmos Sciences (CEX2019-000918-M) and the 'Center of Excellence Severo Ochoa' award for the Instituto de Astrofisica de Andalucia (SEV-2017-0709). A. P. acknowledges financial support from CONACyT and UNAM-PAPIIT IN113119 grant, Mexico.

Context. Most stars form in clusters and thus it is important to characterize the protostellar disk population in dense environments to assess whether the environment plays a role in the subsequent evolution. Specifically, it is critical to evaluate whether planet formation is altered with respect to more isolated stars formed in dark clouds. Aims. We seek to investigate the properties of the protostellar disks in the GGD 27 cluster and compare these with those obtained from disks formed in nearby regions. Methods. We used ALMA to observe the star-forming region GGD 27 at 1.14 mm with an unprecedented angular resolution, 40 mas (∼56 au), and sensitivity (∼0.002 M·). Results. We detected a cluster of 25 continuum sources, most of which likely trace disks around Class 0/I protostars. Excluding the two most massive objects, disks masses are in the range 0.003-0.05 M·. The analysis of the cluster properties indicates that GGD 27 displays moderate subclustering. This result, combined with the dynamical timescale of the radio jet (∼104 years), suggests the youthfulness of the cluster. The lack of disk mass segregation signatures may support this as well. We found a clear paucity of disks with Rdisk > 100 au. The median value of the radius is 34 au; this value is smaller than the median of 92 au for Taurus but comparable to the value found in Ophiuchus and in the Orion Nebula Cluster. In GGD 27 there is no evidence of a distance-dependent disk mass distribution (i.e., disk mass depletion due to external photoevaporation), most likely due to the cluster youth. There is a clear deficit of disks for distances 0.04 pc. This suggests that dynamical interactions far from the cluster center are weaker, although the small disks found could be the result of disk truncation. This work demonstrates the potential to characterize disks from low-mass young stellar objects in distant and massive (still deeply embedded) clustered environments. © 2019 ESO., J.M.T. are supported by the MINECO (Spain) AYA2014-57369-C3 and AYA2017-84390-C2 grants (co-funded by FEDER). G.A. and M.O. acknowledge financial support from the State Agency for Research of the Spanish MCIU through the >Center of Excellence Severo Ochoa> award for the Instituto de Astrofisica de Andalucia (SEV-2017-0709). S.C. acknowledges support from DGAPA, UNAM and CONACyT, Mexico.

Context. We have studied a sample of 89 very isolated, elliptical galaxies at z < 0.08 and compared their properties with elliptical galaxies located in a high-density environment such as the Coma supercluster. Aims. Our aim is to probe the role of environment on the morphological transformation and quenching of elliptical galaxies as a function of mass. In addition, we elucidate the nature of a particular set of blue and star-forming isolated ellipticals identified here. Methods. We studied physical properties of ellipticals, such as color, specific star formation rate, galaxy size, and stellar age, as a function of stellar mass and environment based on SDSS data. We analyzed the blue and star-forming isolated ellipticals in more detail, through photometric characterization using GALFIT, and infer their star formation history using STARLIGHT. Results. Among the isolated ellipticals ≈ 20% are blue, ≤ 8% are star forming, and ≈ 10% are recently quenched, while among the Coma ellipticals ≈ 8% are blue and just ≤ 1% are star forming or recently quenched. There are four isolated galaxies (≈ 4.5%) that are blue and star forming at the same time. These galaxies, with masses between 7 × 10 and 2 × 10 h MO, are also the youngest galaxies with light-weighted stellar ages ≤ 1 Gyr and exhibit bluer colors toward the galaxy center. Around 30-60% of their present-day luminosity, but only red and dead>, although the transition to the red sequence should be faster for isolated ellipticals. In some cases, the isolated environment seems to propitiate the rejuvenation of ellipticals by recent (, acknowledge CONACyT grant (Ciencia Basica) 167332 for partial support. HMHT and J.A.S. acknowledge DGAPA PAPIIT IN-112912 for financial support. A.D.O. acknowledges financial support from the Spanish Ministry for Economy and Competitiveness through grant AYA2013-42227-P and from Junta de Andalucia TIC114.

[Context] The Pipe nebula is a molecular cloud that lacks star formation feedback and has a relatively simple morphology and velocity structure. This makes it an ideal target for testing cloud evolution through collisions., [Aims] We aim at drawing a comprehensive picture of this relatively simple cloud to better understand the formation and evolution of molecular clouds on large scales., [Methods] We use archival data to compare the optical polarization properties, the visual extinction, and the 13CO velocities and linewidths of the entire cloud in order to identify trends among the observables., [Results] The Pipe nebula can be roughly divided into two filaments with different orientations and gas velocity ranges: E–W at 2−4 km s-1 and N–S at 6–7 km s-1. The two filaments overlap at the bowl, where the gas shows a velocity gradient spanning from 2 to 7 km s-1. Compared to the rest of the Pipe nebula, the bowl gas appears to be denser and exhibits larger linewidths. In addition, the polarization data at the bowl shows lower angular dispersion and higher polarization degree. Cores in the bowl tend to cluster in space and to follow the 13CO velocity gradient. In the stem, cores tend to cluster in regions with properties similar to those of the bowl., [Conclusions] The velocity pattern points to a collision between the filaments in the bowl region. The magnetic field seems to be compressed and strengthened in the shocked region. The proportional increase in density and magnetic field strength by a factor similar to the Alfvénic Mach number suggests a continuous shock at low Alfvénic Mach number under the flux-freezing condition. Shocked regions seem to enhance the formation and clustering of dense cores., P.F. is supported by the CONSOLIDER project CSD2009-00038, Spain. P.F. and J.M.G. are supported by the MINECO project AYA2011-30228-C03-02, Spain. G.A.P.F. is supported by the CNPq agency, Brazil. CRZ is supported by program CONACYT CB-2010 152160, México.