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Active galactic nucleus (AGN) bubbles could play an important role in accelerating high-energy cosmic rays (CRs) and galactic feedback. Only in nearby galaxies could we have high enough angular resolution in multiwavelengths to study the sub-kpc environment of the AGN, where the bubbles are produced and strongly interact with the surrounding interstellar medium. In this paper, we present the latest Chandra observations of the Virgo cluster galaxy NGC 4438, which hosts multiscale bubbles detected in various bands. The galaxy also has low current star formation activity, so these bubbles are evidently produced by the AGN rather than a starburst. We present spatially resolved spectral analysis of the Chandra data of the ∼3 arcsec × 5 arcsec (⁠∼200 pc×350 pc⁠) nuclear bubble of NGC 4438. The power-law tail in the X-ray spectra can be most naturally explained as synchrotron emission from high-energy CR leptons. The hot gas temperature increases, while the overall contribution of the non-thermal X-ray emission decreases with the vertical distance from the galactic plane. We calculate the synchrotron cooling time-scale of the CR leptons responsible for the non-thermal hard X-ray emission to be only a few tens to a few hundreds of years. The thermal pressure of the hot gas is about three times the magnetic pressure, but the current data cannot rule out the possibility that they are still in pressure balance. The spatially resolved spectroscopy presented in this paper may have important constraints on how the AGN accelerates CRs and drives outflows. We also discover a transient X-ray source only ∼5 arcsec from the nucleus of NGC 4438. The source was not detected in 2002 and 2008, but became quite X-ray bright in 2020 March, with an average 0.5–7 keV luminosity of ∼1039 erg s−1⁠. © 2022 The Author(s) Published by Oxford University Press on behalf of Royal Astronomical Society., The authors also acknowledge the financial support from NASA and the Chandra X-ray Center through the grant GO9-20074X. TW acknowledges financial support from the coordination of the participation in SKA-SPAIN, financed by the Ministry of Science and Innovation (MCIN), and from the State Agency for Research of the Spanish Ministry of Science, Innovation and Universities through the ‘Centre of Excellence Severo Ochoa’ award to the Instituto de Astrofísica de Andalucía (SEV-2017-0709).

A significant fraction of planetary nebulae (PNe) exhibit collimated outflows, distinct narrow kinematical components with notable velocity shifts with respect to the main nebular shells typically associated with low-ionization compact knots and linear or precessing jet-like features. We present here a spatio-kinematical investigation of a sample of 12 PNe with morphologies in emission lines of low-ionization species suggestive of collimated outflows. Using archival narrow-band images and our own high-dispersion long-slit echelle spectra, we confirm the presence of collimated outflows in Hen 2-429, J 320, M 1-66, M 2-40, M 3-1, and NGC 6210 and possibly in NGC 6741, for which the spatio-kinematical data can also be interpreted as a pair of bipolar lobes. The presence of collimated outflows is rejected in Hen 2-47, Hen 2-115, M 1-26, and M 1-37, but their morphology and kinematics are indicative of the action of supersonic outflows that have not been able to pierce through the nebular envelope. In this sense, M 1-66 appears to have experienced a similar interaction between the outflow and nebular envelope, but, as opposed to these four PNe, the outflow has been able to break through the nebular envelope. It is suggested that the PNe without collimated outflows in our sample are younger or descend from lower mass progenitors than those that exhibit unambiguous collimated outflows. © 2019 The Author(s), JSR-G and MAG acknowledge support of the grants AYA 2014-57280-P and PGC2018-102184-B-I00, co-funded with FEDER funds. SDP acknowledges financial support from the Spanish Ministerio de Econom?a y Competitividad under grants AYA2013 47742-C4-1-P and AYA2016 79724-C4-4-P, from Junta de Andaluc?a Excellence Project PEX2011 FQM-7058. JAT and MAG are also funded by UNAM DGAPA PAPIIT project IA100318. LFM acknowledges partial support by grant AYA2017-84390-C2-R, co-funded with FEDER funds. JSR-G, MAG, LFM, and SDP 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 Astrof?sica de Andaluc?a (SEV-2017-0709). We thank Dr. Laurence Sabin for a thorough reading of the manuscript and her valuable comments that helped us to improve it. Based on observations made with the NASA/ESA Hubble Space Telescope, and obtained from the Hubble Legacy Archive, which is a collaboration between the Space Telescope Science Institute (STScI/NASA), the Space Telescope European Coordinating Facility (STECF/ ESA) and the Canadian Astronomy Data Centre (CADC/NRC/CSA). This research has made also use of the NASA's Astrophysics Data System. This research made use of PYTHON (http://www.python.o rg) and IPYTHON (P?rez, & Granger 2007), APLpy (Robitaille, & Bressert 2012), Numpy (Van Der Walt, Colbert & Varoquaux 2011), Pandas (McKinney 2010), and Matplotlib (Hunter 2007), a suite of open-source PYTHON modules that provides a framework for creating scientific plots. This research made use of Astropy, a community-developed core PYTHON package for Astronomy (Astropy Collaboration et al. 2013). The Astropy web site is http://www.astropy.org.

Dynamics of slender magnetic flux tubes (MFT) in the accretion discs of T Tauri stars is investigated. We perform simulations taking into account buoyant, aerodynamic and turbulent drag forces, radiative heat exchange between MFT and ambient gas, magnetic field of the disc. The equations of MFT dynamics are solved using Runge-Kutta method of the fourth order. The simulations show that there are two regimes of MFT motion in absence of external magnetic field. In the region $r, 18 pages, 12 figures, 3 tables, accepted for publication in MNRAS

We present a sample of 17 objects from the CALIFA survey where we find initial evidence of galactic winds based on their off-axis ionization properties. We identify the presence of outflows using various optical diagnostic diagrams [e.g. EW(Hα), |Nll|/Hα. [Sll]/Hα [OI]/Hα line-ratio maps]. We find that all 17 candidate outflow galaxies lie along the sequence of active star formation in the M∗ versus star-formation rate (SFR) diagram, without a clear excess in the integrated SFR. The location of galaxies along the star-formation main sequence does not influence strongly the presence or not of outflows. The analysis of the SFR density (Σsfr) reveals that the CALIFA sources present higher values when compared with normal star-forming galaxies. The strength of this relation depends on the calibrator used to estimate the SFR. This excess in Σsfr is significant within the first effective radius supporting the idea that most outflows are driven by processes in the inner regions of a galaxy. We find that the molecular gas mass density (Σgas) is a key parameter that plays an important role in the generation of outflows through its association with the local SFR. The canonical threshold reported for the generation of outflows - Σsfr > 0.1 Myrkpc~- is only marginally exceeded in our sample. Within the Kennicutt-Schmidt diagram we propose a domain for galaxies hosting starburst-driven outflows defined ΣSFR > 10MyrI kpc-2 and Σgas > 101Mpcwithin a central kiloparsec region.© 2019 Oxford University Press. All rights reserved., CLC and SFS are grateful for the support of Consejo Nacional de Ciencia y Tecnologia (CONACYT, Mexico) for grant CB-285080, and funding from the PAPIIT-DGAPA-IA101217(UNAM), PAPIIT: IN103318, and CONACYT: 168251 projects. ICG, SFS, and CLC acknowledge support from DGAPA-UNAM (Mexico) grant IN11341. CLC acknowledges CONACYT (Mexico) PhD scholarship. JBH acknowledges the support of anARCLaureate Fellowship

With its bright and wide equatorial waist seen almost edge-on ('the butterfly body') and the faint and broad bipolar extensions ('the butterfly wings'), NGC650-1 is the archetypical example of bipolar planetary nebula (PN) with butterfly morphology. We present here deep high-resolution broad- and narrow-band optical images that expose the rich and intricate fine structure of this bipolar PN, with small-scale bubble-like features and collimated outflows. A SHAPE spatio-kinematic model indicates that NGC650-1 has a broad central torus with an inclination angle of 75° with respect to the line of sight,whereas that of the bipolar lobes,which are clearly seen in the position-velocity maps, is 85°. Large field of view deep images show, for first time, an arc-like diffuse envelope in low- and high-excitation emission lines located up to 180 arcsec towards the east-south-east of the central star, well outside the main nebula. This morphological component is confirmed by Spitzer MIPS and WISE infrared imaging, as well as by long-slit low- and high-dispersion optical spectroscopic observations. Hubble Space Telescope images of NGC650-1 obtained at two different epochs ~14 yr apart reveal the proper motion of the central star along this direction. We propose that this motion of the star through the interstellar medium compresses the remnant material of a slow asymptotic giant branch wind, producing this bow-shock-like feature. © 2017 The Author(s)., GRL acknowledges support from Universidad de Guadalajara (Apoyo de Estancias Academicas - RG/003/2017), CONACyT, CGCI, PRODEP, and SEP (Mexico). MAG also acknowledges support of the grant AYA 2011-29754-C03-02 and AYA 2014-57280-P, both co-funded with FEDER funds. LS acknowledges support from PAPIIT grant IA-101316. Based on observations made with the Observatorio Astronomico Nacional at the Sierra de San Pedro Martir, OAN-SPM, which is operated by the Instituto de Astronomia of the Universidad Nacional Autonoma de Mexico. Also based on observations made with the Nordic Optical Telescope, operated on the island of La Palma jointly by Denmark, Finland, Iceland, Norway, and Sweden, in the Spanish Observatorio del Roque de Los Muchachos of the Instituto de Astrofisica de Canarias. The data presented here were obtained (in part) with ALFOSC, which is provided by the Instituto de Astrofisica de Andalucia (IAA) under a joint agreement with the University of Copenhagen and NOTSA. This paper is based on observations made with the IAC80 operated on the island of Tenerife by the IAC in the Spanish Observatorio del Teide. Also based on observations made with the Gran Telescopio Canarias (GTC), installed in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astroffsica de Canarias, in the island of La Palma. This publication makes use of data products from the Wide-field Infrared Survey Explorer, which is a joint project of the University of California, Los Angeles, and the Jet Propulsion Laboratory/California Institute of Technology, funded by the National Aeronautics and Space Administration. This work is based (in part) on observations made with the Spitzer Space Telescope, which is operated by the Jet Propulsion Laboratory, California Institute of Technology under a contract with NASA. IRAF, the Image Reduction and Analysis Facility, is distributed by the National Optical Astronomy Observatory, which is operated by the Association of Universities for Research in Astronomy (AURA) under cooperative agreement with the National Science Foundation. XVISTA is an interactive image and spectral reduction and analysis package developed at the Lick Observatory and maintained and distributed by Jon Holtzman at the New Mexico State University at http://ganymede.nmsu.edu/holtz/xvista/.

Jet ejection by accreting black holes is a mass invariant mechanism unifying stellar and supermassive black holes (SMBHs) that should also apply for intermediate-mass black holes (IMBHs), which are thought to be the seeds from which SMBHs form. We present the detection of an off-nuclear IMBH of $\sim$5 $\times$ 10$^{4}$ M$_\odot$ located in an unusual spiral arm of the galaxy NGC 2276 based on quasi-simultaneous \textit{Chandra} X-ray observations and European VLBI Network (EVN) radio observations. The IMBH, NGC2276-3c, possesses a 1.8 pc radio jet that is oriented in the same direction as large-scale ($\sim$650 pc) radio lobes and whose emission is consistent with flat to optically thin synchrotron emission between 1.6 GHz and 5 GHz. Its jet kinetic power ($4 \times 10^{40}$ erg s$^{-1}$) is comparable to its radiative output and its jet efficiency ($\geq$ 46\%) is as large as that of SMBHs. A region of $\sim$300 pc along the jet devoid of young stars could provide observational evidence of jet feedback from an IMBH. The discovery confirms that the accretion physics is mass invariant and that seed IMBHs in the early Universe possibly had powerful jets that were an important source of feedback., Comment: 7 pages, 2 figures, accepted for publication in MNRAS