Context. The point spread function of the integral field unit (IFU) mode of the Near-Infrared Spectrograph (NIRSpec) detector of JWST is undersampled. The resampling of the spectra into a 3D data cube creates resampling noise seen as low-frequency sinusoidal-like artifacts, or "wiggles." These artifacts in the data are not corrected in the JWST data pipeline and significantly impact the science that can be achieved at a single-pixel level. Aims. Here we present the tool "WIggle Corrector Kit for NIRSpEc Data" (WICKED) designed to remove these artifacts. While fully characterizing wiggles requires forward modeling of the instrument response, WICKED offers a faster and computationally efficient alternative using an empirical correction. Methods. WICKED uses the fast Fourier transform algorithm to identify wiggle-affected spaxels across the (IFU) data cube. Spectra are modeled with a mix of integrated aperture and annular templates, a power law, and a second-degree polynomial, thus avoiding the high-degree polynomials that distort spectral features. Our correction works across all medium- and high-resolution NIRSpec gratings: F070LP, F100LP, F170LP, and F290LP. Results. The overall spectral shape recovered by WICKED is up to 3.5 times better compared to uncorrected spectra. It recovers the equivalent width of absorption lines within 5% of the true value, which is also roughly three times better than the uncorrected spectra. WICKED7 significantly improves kinematic measurements, recovering the line-of-sight velocity (LOSV) within 1% of the true value - more than 100 times better than uncorrected spectra at S/N similar to 40. As a case study, we applied WICKED to G235H/F170LP IFU data of the elliptical galaxy NGC 5128, finding good agreement with previous studies. In wiggle-affected regions, the uncorrected spectrum showed a stellar LOSV and velocity dispersion differences similar to 17 times and similar to 36 times larger than the estimated uncertainties, respectively, compared to the WICKED-cleaned spectrum. Conclusions. Wiggles in NIRSpec IFU data can significantly distort the overall spectral shape and bias line measurements and kinematics to values larger than the expected uncertainties for uncorrected spectra. WICKED is a robust, user-friendly solution for mitigating wiggles in NIRSpec data that enables precise single-spaxel studies and enhances JWST's potential for groundbreaking discoveries in galaxy kinematics and early Universe studies.

Tidal disruption events (TDEs) are a class of transients that occur when a star is destroyed by the tides of a massive black hole (MBH). Their rates encode valuable MBH demographic information, but this can only be extracted if accurate TDE rate predictions are available for comparisons with observed rates. In this work, we present a new, observer-friendly Python package called REPTiDE, which implements a standard loss-cone model for computing TDE rates given a stellar density distribution and an MBH mass. We apply this software to a representative sample of 91 nearby galaxies over a wide range of stellar masses with high-resolution nuclear density measurements from C. H. Hannah et al. We measure per-galaxy TDE rates ranging between 10 ^−7.7 and 10 ^−2.9 yr ^–1 and find that the sample-averaged rates agree well with observations. We find a turnover in the TDE rate as a function of both galaxy stellar mass and black hole mass, with the peak rates being observed in galaxies at a galaxy mass of 10 ^9.5 M _⊙ and a black hole mass of 10 ^6.5 M _⊙ . Despite the lower TDE rates inferred for intermediate-mass black holes, we find that they have gained a higher fraction of their mass through TDEs when compared to higher-mass black holes. This growth of lower-mass black holes through TDEs can enable us to place interesting constraints on their spins; we find maximum spins of a _• ≈ 0.9 for black holes with masses below ∼10 ^5.5 M _⊙ .

The black hole occupation fraction (f(occ)) defines the fraction of galaxies that harbor central massive black holes (MBHs), irrespective of their accretion activity level. While it is widely accepted that f(occ) is nearly 100% in local massive galaxies with stellar masses M star greater than or similar to 10(10) M-circle dot, it is not yet clear whether MBHs are ubiquitous in less-massive galaxies. In this work, we present new constraints on f(occ) based on over 20 yr of Chandra imaging data for 1606 galaxies within 50 Mpc. We employ a Bayesian model to simultaneously constrain f(occ )and the specific accretion-rate distribution function, p(lambda), where the specific accretion rate is defined as lambda = L-X/M-star, where L-X is the MBH accretion luminosity in the 2-10 keV range. Notably, we find that p(lambda) peaks around 10(28)ergs(-1)M circle dot(-1) ; above this value, p(lambda) decreases with increasing lambda, following a power law that smoothly connects with the probability distribution of bona fide active galactic nuclei. We also find that the occupation fraction decreases dramatically with decreasing M-star: in high-mass galaxies (M-star approximate to 10(11-12 )M(circle dot)), the occupation fraction is >93% (a 2 sigma lower limit), and then declines to 66%-7%+8% (1 sigma errors) between M-star approximate to 10(9-10) M-circle dot,M- and to 33%(+13%)(-9%) in the dwarf galaxy regime between M-star approximate to 10(8-9 )M(circle dot). Our results have significant implications for the normalization of the MBH mass function over the mass range most relevant for tidal disruption events, extreme mass ratio inspirals, and MBH merger rates that upcoming facilities are poised to explore.

Context. The Galactic centre (GC) region contains a dense accumulation of stars that can be separated into two components: a mildly flattened and extremely dense nuclear star cluster (NSC) and a surrounding more extended and more flattened nuclear stellar disc (NSD). Previous studies have collected a few thousand spectra of the inner NSC and the outer NSD and have measured line-of-sight velocities and metallicities. Until now, such measurements exist only for a few hundred stars in the region where the stellar surface density transitions from being dominated by the NSC to being dominated by the NSD. Aims. We seek to study the stellar population from the centre of the NSC out to well beyond its effective radius, where the NSD dominates. In this way, we can investigate whether and how the mean properties and kinematics of the stars change systematically. Methods. We conducted spectroscopic observations with Flamingos-2 in the K -band via a continuous slit scan. The data extend from the central NSC to the inner NSD, out to ±32 pc from Sgr A ★ along Galactic longitude l . Based on their CO equivalent widths, we classified the stars in these areas as hot or cool stars. The former are massive young stars, while almost all of the latter are older than one to a few gigayears. Applying full-spectral fitting, we measured the overall metallicity [M/H] and line-of-sight velocity V LOS for more than 2500 cool stars, increasing existing samples outside of the very centre by a factor of three in terms of the number of stars and by more than an order of magnitude in terms of covered area. We present the first continuous spatial maps and profiles of the mean value of various stellar and kinematic parameters. Results. We identify hot young stars across the field of view. Some stars appear to be isolated from other hot stars, while others accumulate within 2.7 pc of the Quintuplet cluster, or the central parsec cluster. The position-velocity curve of the cool stars shows no dependence on [M/H], but it depends on the colour of the stars. The colour may be a tracer of the line-of-sight distance and thus distinguish stars located in the NSC from those in the NSD. A subset of the cool stars has high velocities (i.e. greater than 150 km s −1 ), and they may be associated with the bar or tidal tails of star clusters.

The fraction of local dwarf galaxies that hosts massive black holes is arguably the cleanest diagnostic of the dominant seed formation mechanism of today's supermassive black holes. A 5 per cent constraint on this quantity can be achieved with AXIS observations of 3300 galaxies across the mass spectrum through a combination of serendipitous extra-galactic fields plus a dedicated 1 Msec GO program.

Leiden Observatory, Leiden University, The Netherlands Center for Astrophysics and Cosmology, University of Nova Gorica, Slovenia Institute for Gravitational Wave Astronomy and School of Physics and Astronomy, University of Birmingham, Birmingham B15 2TT, UK School of Physics, The University of Melbourne, Parkville, VIC 3010, Australia Space Telescope Science Institute, Baltimore, USA Monash Centre for Astrophysics, School of Physics and Astronomy, Monash University, Clayton, Victoria 3800, Australia Department of Physics and Astronomy, University of Utah, Salt Lake City, USA

Star Clusters with the Evolution of Their Early and Late-type Hosts” (2021, ApJ, 921, 8) Francesca Pinna , Nadine Neumayer , Anil Seth , Eric Emsellem , Dieu D. Nguyen , Torsten Böker , Michele Cappellari , Richard M. McDermid , Karina Voggel , and C. Jakob Walcher 1 Max Planck Institute for Astronomy, D-69117 Heidelberg, Germany; pinna@mpia.de 2 Department of Physics and Astronomy, University of Utah, UT 84112, USA 3 European Southern Observatory, D-85748 Garching bei Muenchen, Germany 4 National Astronomical Observatory of Japan (NAOJ), National Institute of Natural Sciences (NINS), 2-21-1 Osawa, Mitaka, Tokyo 181-8588, Japan 5 European Space Agency/STScI, Baltimore, MD 21218, USA 6 Department of Physics, University of Oxford, OX1 3RH, UK 7 Research Centre for Astronomy, Astrophysics, and Astrophotonics, Macquarie University, Sydney, NSW 2109, Australia 8 Universite de Strasbourg, CNRS, Observatoire astronomique de Strasbourg, UMR 7550, F-67000 Strasbourg, France 9 Leibniz-Institut für Astrophysik Potsdam (AIP) D-14482 Potsdam, Germany Received 2021 December 2; published 2021 December 29

The improper use of artificial light causing skyglow is detrimental to many types of wildlife and can potentially cause irregular human sleeping patterns. Studies have been performed to analyze light pollution on a global scale. However, light pollution data on a local scale is not often available and the effects at local scale have rarely been studied. Herein, a new custom-designed autonomous light assessment drone (ALAD) is described for evaluating light pollution at local scale. The ALAD is designed and equipped with a sky quality meter (SQM) to measure skyglow and a low-cost illuminance sensor to measure light from artificial sources. Outdoor field tests are performed at a remote site in central Utah and the measured results are validated against data from lightpollution-map.info. The SQM measurements are in agreement with the estimates from the light pollution map, and the initial results demonstrate feasibility of the ALAD for local-scale skyglow assessment.

Supermassive black holes are located at the center of most, if not all, massive galaxies. They follow close correlations with global properties of their host galaxies (scaling relations), and are thought to play a crucial role in galaxy evolution. Yet, we lack a complete understanding of fundamental aspects of their growth across cosmic time. In particular, we still do not understand: (1) whether black holes or their host galaxies grow faster and (2) what is the maximum mass that black holes can reach. The high angular resolution capability and sensitivity of 30-m class telescopes will revolutionize our understanding of the extreme end of the black hole and galaxy mass scale. With such facilities, we will be able to dynamically measure masses of the largest black holes and characterize galaxy properties out to redshift $z \sim 1.5$. Together with the evolution of black hole-galaxy scaling relations since $z \sim 1.5$, the maximum mass black hole will shed light on the main channels of black hole growth.

We measure the recent star formation history (SFH) across M31 using optical images taken with the Hubble Space Telescope as part of the Panchromatic Hubble Andromeda Treasury (PHAT). We fit the color-magnitude diagrams in similar to 9000 regions that are similar to 100 pc x 100 pc in projected size, covering a 0.5 square degree area (similar to 380 kpc(2), deprojected) in the NE quadrant of M31. We show that the SFHs vary significantly on these small spatial scales but that there are also coherent galaxy-wide fluctuations in the SFH back to similar to 500 Myr, most notably in M31's 10 kpc star-forming ring. We find that the 10 kpc ring is at least 400 Myr old, showing ongoing star formation (SF) over the past similar to 500 Myr. This indicates the presence of molecular gas in the ring over at least 2 dynamical times at this radius. We also find that the ring's position is constant throughout this time, and is stationary at the level of 1 km s(-1), although there is evidence for broadening of the ring due to the diffusion of stars into the disk. Based on existing models of M31's ring features, the lack of evolution in the ring's position makes a purely collisional ring origin highly unlikely. Besides the well-known 10 kpc ring, we observe two other ring-like features. There is an outer ring structure at 15 kpc with concentrated SF starting similar to 80 Myr ago. The inner ring structure at 5 kpc has a much lower star formation rate (SFR) and therefore lower contrast against the underlying stellar disk. It was most clearly defined similar to 200 Myr ago, but is much more diffuse today. We find that the global SFR has been fairly constant over the last similar to 500 Myr, though it does show a small increase at 50 Myr that is 1.3 times the average SFR over the past 100 Myr. During the last similar to 500 Myr, similar to 60% of all SF has occurred in the 10 kpc ring. Finally, we find that in the past 100 Myr, the average SFR over the PHAT survey area is 0.28 +/- 0.03 M-circle dot yr(-1) with an average deprojected intensity of 7.3 x 10(-4) M-circle dot yr(-1) kpc(-2), which yields a total SFR of similar to 0.7 M-circle dot yr(-1) when extrapolated to the entire area of M31's disk. This SFR is consistent with measurements from broadband estimates.

We present scaling relations between structural properties of nuclear star clusters and their host galaxies for a sample of early-type dwarf galaxies observed as part of the Hubble Space Telescope (HST) Advanced Camera for Surveys (ACS) Coma Cluster Survey. We have analysed the light profiles of 200 early-type dwarf galaxies in the magnitude range 16.0 < mF814W < 22.6 mag, corresponding to −19.0 < MF814W < −12.4 mag. Nuclear star clusters are detected in 80 per cent of the galaxies, thus doubling the sample of HST-observed early-type dwarf galaxies with nuclear star clusters. We confirm that the nuclear star cluster detection fraction decreases strongly towards faint magnitudes. The luminosities of nuclear star clusters do not scale linearly with host galaxy luminosity. A linear fit yields Lnuc ∼ L0.57±0.05 gal . The nuclear star cluster–host galaxy luminosity scaling relation for low-mass early-type dwarf galaxies is consistent with formation by globular cluster (GC) accretion. We find that at similar luminosities, galaxies with higher Sérsic indices have slightly more luminous nuclear star clusters. Rounder galaxies have on average more luminous clusters. Some of the nuclear star clusters are resolved, despite the distance of Coma. We argue that the relation between nuclear star cluster mass and size is consistent with both formation by GC accretion and in situ formation. Our data are consistent with GC inspiralling being the dominant mechanism at low masses, although the observed trend with Sérsic index suggests that in situ star formation is an important second-order effect.