Nora Lützgendorf

We present near- and mid-infrared spectra of eight low-luminosity active galactic nuclei (LLAGN), spanning nearly 4 orders of magnitude in black hole mass and Eddington ratio, obtained with JWST/NIRSpec and MIRI as part of the ReveaLLAGN program, along with identical archival data of Cen A. The high spatial resolution of JWST cleanly separates active galactic nuclei (AGN) emission from host-galaxy contamination, enabling detections of high-ionization-potential lines more than an order of magnitude fainter than previously measured. Emission-line diagnostics reveal a transition at log( L _bol / L _Edd ) ∼−3.5, where the spectral energy distribution becomes increasingly deficient in ultraviolet photons. We find that rotational H ₂ excitation temperatures are elevated (∼500 K higher) compared to both higher-luminosity AGN and star-forming galaxies, while the H ₂ (0–0)S(3)/PAH _{11.3 μ m} ratios are consistent with those observed in the AGN population. We discuss the possible roles of outflows, jets, and X-ray-dominated regions in shaping the interstellar medium surrounding LLAGN. Silicate emission at ∼10 μ m, localized to the nuclear region, is detected in most ReveaLLAGN targets. This dataset offers the first comprehensive JWST-based characterization of infrared emission lines in the nuclear regions of LLAGN.

We present an overview of the James Webb Space Telescope (JWST) Advanced Deep Extragalactic Survey (JADES), an ambitious program of infrared imaging and spectroscopy in the GOODS-S and GOODS-N deep fields, designed to study galaxy evolution from high redshift to cosmic noon. JADES uses about 770 hr of Cycle 1 guaranteed time largely from the Near-Infrared Camera (NIRCam) and Near-Infrared Spectrograph (NIRSpec) instrument teams. In GOODS-S, in and around the Hubble Ultra Deep Field and Chandra Deep Field South, JADES produces a deep imaging region of ∼42 arcmin ² with over 100 hr of exposure time spread over nine NIRCam filters, including two medium-band filters. This is extended at medium depth in GOODS-S and GOODS-N with NIRCam imaging of ∼167 arcmin ² , averaging 25 hr of exposure over 8–10 filters. In both fields, we conduct extensive NIRSpec multiobject spectroscopy, including two deep pointings of 55 hr exposure time, 14 medium pointings of ∼12 hr, and 15 shallower pointings of ∼4 hr, targeting over 5000 Hubble Space Telescope– and JWST-detected faint sources with five low-, medium-, and high-resolution dispersers covering 0.6–5.3 μ m. Finally, JADES extends redward via coordinated parallels with the JWST Mid-Infrared Instrument, featuring ∼10 arcmin ² with 43 hr of exposure at 7.7 μ m and thrice that area with 1.4–6.8 hr of exposure at 12.8 and 15 μ m. For nearly 30 yr, the GOODS-S and GOODS-N fields have been developed as the premier deep fields on the sky; JADES is now providing a compelling start on JWST's legacy in these fields.

We summarize the properties and initial data release of the JADES Origins Field (JOF), the longest single pointing yet imaged with the James Webb Space Telescope (JWST). This field falls within the GOODS-S region about 8′ southwest of the Hubble Ultra Deep Field (HUDF), where it was formed initially in Cycle 1 as a parallel field of HUDF spectroscopic observations within the JWST Advanced Deep Extragalactic Survey (JADES). This imaging was greatly extended in Cycle 2 program 3215, which observed the JOF for 5 days in six medium-band filters, seeking robust candidates for z > 15 galaxies. This program also includes ultradeep parallel NIRSpec spectroscopy (up to 91 hr on source, summing over the dispersion modes) on the HUDF. Cycle 3 observations from program 4540 added 20 hr of NIRCam slitless spectroscopy and F070W imaging to the JOF. With these three campaigns, the JOF was observed for 380 open-shutter hours with NIRCam using 15 imaging filters and two grism bandpasses. Further, parts of the JOF have deep 43 hr MIRI observations in F770W. Taken together, the JOF is one of the most compelling deep fields available with JWST and a powerful window into the early Universe. This paper presents the second data release from JADES, featuring the imaging and catalogs from the year 1 JOF observations.

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 “ WI ggle C orrector K it for NIRSp E c D ata” (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 ~ 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 ~17 times and ~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.

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.

We present the first results from the Revealing Low-Luminosity Active Galactic Nuclei (ReveaLLAGN) survey, a JWST survey of seven nearby LLAGNs. We focus on two observations with the Mid-Infrared Instrument (MIRI)’s Medium-Resolution Spectrometer of the nuclei of NGC 1052 and Sombrero (NGC 4594/M104). We also compare these data to public JWST data of higher-luminosity AGNs, NGC 7319 and NGC 7469. JWST clearly separates the AGN spectrum from the galaxy light even in Sombrero, the faintest target in our survey; the AGN components have very red spectra. We find that the emission-line widths in both NGC 1052 and Sombrero increase with increasing ionization potential, with FWHM > 1000 km s⁻¹ for lines with ionization potential ≳ 50 eV. These lines are also significantly blueshifted in both LLAGNs. The high-ionization-potential lines in NGC 7319 show neither broad widths nor significant blueshifts. Many of the lower-ionization-potential emission lines in Sombrero show significant blue wings extending >1000 km s⁻¹. These features and the emission-line maps in both galaxies are consistent with outflows along the jet direction. Sombrero has the lowest-luminosity high-ionization-potential lines ([Ne v] and [O iv]) ever measured in the mid-infrared, but the relative strengths of these lines are consistent with higher-luminosity AGNs. On the other hand, the [Ne v] emission is much weaker relative to the [Ne iii] and [Ne ii] lines of higher-luminosity AGNs. These initial results show the great promise that JWST holds for identifying and studying the physical nature of LLAGNs.

Spectra of young benchmark brown dwarfs with well-known ages are vital to characterize other brown dwarfs, for which ages are in general not known. These spectra are also crucial to test atmospheric models, which have the potential to provide detailed information about the atmospheres of these objects. However, to test atmospheric models optimally, medium-resolution, long-wavelength-coverage spectra with well-understood uncertainties are ideal, such as the spectra provided by the NIRSpec instrument on board the James Webb Space Telescope. In this paper, we present medium-resolution JWST/NIRSpec spectra of two young brown dwarfs, TWA 28 (M9.0) and TWA 27A (M9.0), and one planetary-mass object, TWA 27B (L6.0), members of the TW Hydrae Association (age ∼ 10 Myr). We show the richness of the atomic lines and molecular bands present in the spectra. All objects show signs of a circumstellar disk, via a near-infrared excess and/or via emission lines. We matched a set of cloudless atmospheric spectra (ATMO), and cloudy atmospheric spectra (BT-Settl) to our NIRSpec spectra, and analyzed which wavelength ranges and spectral features both models reproduce best. Both models derive consistent parameters for the three sources, and predict the existence of CH₄ at 3.35 μm in TWA 27B. Nonetheless, in contrast to other slightly older objects with similar spectral type, like PSO 318.5–22 and VHS 1256b, this feature is not present in the spectrum of TWA 27B. The lack of the CH₄ feature might suggest that the L–T transition of very young dwarfs starts at later spectral types than for older brown dwarfs.

We present the first results from the Revealing Low-Luminosity Active Galactic Nuclei (ReveaLLAGN) survey, a JWST survey of seven nearby LLAGN. We focus on two observations with the Mid-Infrared Instrument's (MIRI) Medium Resolution Spectrograph (MRS) of the nuclei of NGC 1052 and Sombrero (NGC 4594 / M104). We also compare these data to public JWST data of a higher-luminosity AGN, NGC 7319 and NGC 7469. JWST clearly separates the AGN spectrum from the galaxy light even in Sombrero, the faintest target in our survey; the AGN components have very red spectra. We find that the emission-line widths in both NGC 1052 and Sombrero increase with increasing ionization potential, with FWHM > 1000 km/s for lines with ionization potential > 50 eV. These lines are also significantly blue-shifted in both LLAGN. The high ionization potential lines in NGC 7319 show neither broad widths or significant blue shifts. Many of the lower ionization potential emission lines in Sombrero show significant blue wings extending > 1000 km/s. These features and the emission-line maps in both galaxies are consistent with outflows along the jet direction. Sombrero has the lowest luminosity high-ionization potential lines ([Ne V] and [O IV]) ever measured in the mid-IR, but the relative strengths of these lines are consistent with higher luminosity AGN. On the other hand, the [Ne V] emission is much weaker relative to the [Ne III] and [Ne II] lines of higher-luminosity AGN. These initial results show the great promise that JWST holds for identifying and studying the physical nature of LLAGN.

Quasar-driven galactic outflows are a major driver of the evolution of massive galaxies. We report observations of a powerful galactic-scale outflow in a z = 3 extremely red and intrinsically luminous (L _bol ≃ 5 × 10⁴⁷erg s⁻¹) quasar SDSSJ1652 + 1728 with the Near-infrared Spectrograph on board JWST. We analyze the kinematics of rest-frame optical emission lines and identify the quasar-driven outflow extending out to ∼10 kpc from the quasar with a velocity offset of (v _r = ± 500 km s⁻¹) and high velocity dispersion (FWHM = 700–2400 km s⁻¹). Due to JWST’s unprecedented surface brightness sensitivity in the near-infrared, we unambiguously show that the powerful high velocity outflow in an extremely red quasar encompasses a large swath of the host galaxy’s interstellar medium. Using the kinematics and dynamics of optical emission lines, we estimate the mass outflow rate—in the warm ionized phase alone—to be at least 2300 ± 1400 M _⊙ yr⁻¹. We measure a momentum flux ratio between the outflow and the quasar accretion disk of ∼1 on a kpc scale, indicating that the outflow was likely driven in a relatively high (>10²³cm⁻²) column density environment through radiation pressure on dust grains. We find a coupling efficiency between the bolometric luminosity of the quasar and the outflow of 0.1%, matching the theoretical prediction of the minimum coupling efficiency necessary for negative quasar feedback. The outflow has sufficient energetics to drive the observed turbulence seen in shocked regions of the quasar host galaxy, which are likely directly responsible for prolonging the time that it takes for gas to cool efficiently.

We summarize the properties and initial data release of the JADES Origins Field (JOF), which will soon be the deepest imaging field yet observed with the James Webb Space Telescope (JWST). This field falls within the GOODS-S region about 8' south-west of the Hubble Ultra Deep Field (HUDF), where it was formed initially in Cycle 1 as a parallel field of HUDF spectroscopic observations within the JWST Advanced Deep Extragalactic Survey (JADES). This imaging will be greatly extended in Cycle 2 program 3215, which will observe the JOF for 5 days in six medium-band filters, seeking robust candidates for z>15 galaxies. This program will also include ultra-deep parallel NIRSpec spectroscopy (up to 104 hours on-source, summing over the dispersion modes) on the HUDF. Cycle 3 observations from program 4540 will add 20 hours of NIRCam slitless spectroscopy to the JOF. With these three campaigns, the JOF will be observed for 380 open-shutter hours with NIRCam using 15 imaging filters and 2 grism bandpasses. Further, parts of the JOF have deep 43 hr MIRI observations in F770W. Taken together, the JOF will soon be one of the most compelling deep fields available with JWST and a powerful window into the early Universe. This paper presents the second data release from JADES, featuring the imaging and catalogs from the year 1 JOF observations.