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Irene Shivaei

Publications and source records attributed to Irene Shivaei.

At least 91 records · Page 5Linked to original sources
arXiv2024

The SMILES Mid-Infrared Survey

The Mid-Infrared Instrument (MIRI) for JWST is supplied with a suite of imaging bandpass filters optimized for full spectral coverage in eight intermediate-width bands from 5 to 26 microns and a narrower one at 11.3 microns. This contrasts with previous infrared space telescopes, which generally have provided only two broad bands, one near 10 microns and the other near 20 microns. The expanded MIRI spectral capability provides new possibilities for detailed interpretation of survey results. This is an important feature of the instrument, on top of its great increase in sensitivity and angular resolution over any previous mission. The Systematic Mid-infrared Instrument Legacy Extragalactic Survey (SMILES) was designed to take full advantage of this capability. This paper briefly describes the history of infrared surveys that paved the way for MIRI on JWST and for our approach to designng SMILES. It illustrates the use of the observations for a broad range of science programs, and concludes with a brief summary of the need for additional surveys with JWST/MIRI.

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arXiv2024

SMILES Initial Data Release: Unveiling the Obscured Universe with MIRI Multi-band Imaging

The James Webb Space Telescope (JWST) is revolutionizing our view of the Universe through unprecedented sensitivity and resolution in the infrared, with some of the largest gains realized at its longest wavelengths. We present the Systematic Mid-infrared Instrument (MIRI) Legacy Extragalactic Survey (SMILES), an eight-band MIRI survey with Near-Infrared Spectrograph (NIRSpec) spectroscopic follow-up in the GOODS-S/HUDF region. SMILES takes full advantage of MIRI's continuous coverage from $5.6-25.5\,μ$m over a $\sim34$ arcmin$^2$ area to greatly expand our understanding of the obscured Universe up to cosmic noon and beyond. This work, together with a companion paper by Rieke et al., covers the SMILES science drivers and technical design, early results with SMILES, data reduction, photometric catalog creation, and the first data release. As part of the discussion on early results, we additionally present a high-level science demonstration on how MIRI's wavelength coverage and resolution will advance our understanding of cosmic dust using the full range of polycyclic aromatic hydrocarbon (PAH) emission features from $3.3-18\,μ$m. Using custom background subtraction, we produce robust reductions of the MIRI imaging that maximize the depths reached with our modest exposure times ($\sim0.6 - 2.2$ ks per filter). Included in our initial data release are (1) eight MIRI imaging mosaics reaching depths of $0.2-18\,μ$Jy ($5σ$) and (2) a $5-25.5\,μ$m photometric catalog with over 3,000 sources. Building upon the rich legacy of extensive photometric and spectroscopy coverage of GOODS-S/HUDF from the X-ray to the radio, SMILES greatly expands our investigative power in understanding the obscured Universe.

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arXiv2024

AGN Selection and Demographics: A New Age with JWST/MIRI

Understanding the co-evolution of supermassive black holes (SMBHs) and their host systems requires a comprehensive census of active galactic nuclei (AGN) behavior across a wide range of redshift, luminosity, obscuration level and galaxy properties. We report significant progress with JWST towards this goal from the Systematic Mid-infrared Instrument Legacy Extragalactic Survey (SMILES). Based on comprehensive SED analysis of 3273 MIRI-detected sources, we identify 217 AGN candidates over a survey area of $\sim$34 arcmin$^2$, including a primary sample of 111 AGNs in normal massive galaxies ($M_{*}>10^{9.5}~M_\odot$) at $z\sim$0--4, an extended sample of 86 AGN {\it candidates} in low-mass galaxies ($M_{*}<10^{9.5}~M_\odot$) and a high-$z$ sample of 20 AGN {\it candidates} at $z\sim$4--8.4. Notably, about 80\% of our MIRI-selected AGN candidates are new discoveries despite the extensive pre-JWST AGN searches. Even among the massive galaxies where the previous AGN search is believed to be thorough, 34\% of the MIRI AGN identifications are new, highlighting the impact of obscuration on previous selections. By combining our results with the efforts at other wavelengths, we build the most complete AGN sample to date and examine the relative performance of different selection techniques. We find the obscured AGN fraction increases from $L_{\rm AGN, bol}\sim10^{10}~L_\odot$ to $10^{11}~L_\odot$ and then drops towards higher luminosity. Additionally, the obscured AGN fraction gradually increases from $z\sim0$ to $z\sim4$ with most high-$z$ AGNs obscured. We discuss how AGN obscuration, intrinsic SED variations, galaxy contamination, survey depth and selection techniques complicate the construction of a complete AGN sample.

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arXiv2024

JADES Data Release 3 -- NIRSpec/MSA spectroscopy for 4,000 galaxies in the GOODS fields

We present the third data release of JADES, the JWST Advanced Deep Extragalactic Survey, providing both imaging and spectroscopy in the two GOODS fields. Spectroscopy consists of medium-depth and deep NIRSpec/MSA spectra of 4,000 targets, covering the spectral range 0.6-5.3 $μ$m and observed with both the low-dispersion prism (R=30-300) and all three medium-resolution gratings (R=500-1,500). We describe the observations, data reduction, sample selection, and target allocation. We measured 2,375 redshifts (2,053 from multiple emission lines); our targets span the range from z=0.5 up to z=13, including 404 at z>5. The data release includes 2-d and 1-d fully reduced spectra, with slit-loss corrections and background subtraction optimized for point sources. We also provide redshifts and S/N>5 emission-line flux catalogs for the prism and grating spectra, and concise guidelines on how to use these data products. Alongside spectroscopy, we are also publishing fully calibrated NIRCam imaging, which enables studying the JADES sample with the combined power of imaging and spectroscopy. Together, these data provide the largest statistical sample to date to characterize the properties of galaxy populations in the first billion years after the Big Bang.

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arXiv2024

What is the nature of Little Red Dots and what is not, MIRI SMILES edition

We study little red dots (LRD) detected by JADES and covered by the SMILES MIRI survey. Our sample contains 31 sources, $\sim70$% detected in the two bluest MIRI bands, 40% in redder filters. The median/quartiles redshifts are $z=6.9_{5.9}^{7.7}$ (55% spectroscopic). We analyze the rest-frame ultraviolet through near/mid-infrared spectral energy distributions of LRDs combining NIRCam and MIRI observations, using a variety of modeling techniques that include emission from stars, dust, and (un)obscured active galactic nuclei (AGN). The NIRCam$-$MIRI colors, for $\geq10$ $μ$m, are bluer than direct pure emission from AGN tori; the spectral slope flattens in the rest-frame near-infrared, consistent with a 1.6 $μ$m stellar bump. Both observations imply that stellar emission makes the dominant contribution at these wavelengths, expediting a stellar mass estimation: the median/quartiles are $\log \mathrm{M_\star/M_\odot}=9.4_{9.1}^{9.7}$. The number density of LRDs is $10^{-4.0\pm0.1}$ Mpc$^{-3}$, accounting for $14\pm3$% of the global population of galaxies with similar redshifts and masses. The flat ultraviolet spectral range is dominated by young stars. The rest-frame near/mid-infrared (2-4 $μ$m) spectral slope reveals significant amounts of dust (bolometric stellar attenuation $\sim3-4$ mag) heated by strong radiation fields arising from highly embedded compact sources. Our models imply $<0.4$ kpc heating knots, containing dust-enshrouded OB stars or an AGN producing a similar radiation field, obscured by $\mathrm{A(V)}>10$ mag. We conclude that LRDs are extremely intense and compact starburst galaxies with mass-weighted ages 5-10 Myr, very efficient in producing dust, their global energy output dominated by the direct and dust-recycled emission from OB stars, with some contribution from obscured AGN in the mid-infrared.

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arXiv2024

JWST MIRI Flight Performance: Imaging

The Mid-Infrared Instrument (MIRI) aboard the James Webb Space Telescope (JWST) provides the observatory with a huge advance in mid-infrared imaging and spectroscopy covering the wavelength range of 5 to 28 microns. This paper describes the performance and characteristics of the MIRI imager as understood during observatory commissioning activities, and through its first year of science operations. We discuss the measurements and results of the imager's point spread function, flux calibration, background, distortion and flat fields as well as results pertaining to best observing practices for MIRI imaging, and discuss known imaging artefacts that may be seen during or after data processing. Overall, we show that the MIRI imager has met or exceeded all its pre-flight requirements, and we expect it to make a significant contribution to mid-infrared science for the astronomy community for years to come.

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arXiv2024

A recently quenched galaxy 700 million years after the Big Bang

Local and low-redshift ($z$<$3$) galaxies are known to broadly follow a bimodal distribution: actively star forming galaxies with relatively stable star-formation rates, and passive systems. These two populations are connected by galaxies in relatively slow transition. In contrast, theory predicts that star formation was stochastic at early cosmic times and in low-mass systems: these galaxies transitioned rapidly between starburst episodes and phases of suppressed star formation, potentially even causing temporary quiescence -- so-called mini-quenching events. However, the regime of star-formation burstiness is observationally highly unconstrained. Directly observing mini-quenched galaxies in the primordial Universe is therefore of utmost importance to constrain models of galaxy formation and transformation. Early quenched galaxies have been identified out to redshift $z<5$, and these are all found to be massive ($M_{*}>10^{10}~M_{\odot}$) and relatively old. Here we report a (mini-)quenched galaxy at z$=$7.3, when the Universe was only 700~Myr old. The JWST/NIRSpec spectrum is very blue ($U$-$V$$=$0.16$\pm0.03$~mag), but exhibits a Balmer break and no nebular emission lines. The galaxy experienced a short starburst followed by rapid quenching; its stellar mass (4-6$\times 10^8~M_\odot$) falls in a range that is sensitive to various feedback mechanisms, which can result in perhaps only temporary quenching.

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arXiv2024

Little Red Dots: an abundant population of faint AGN at z~5 revealed by the EIGER and FRESCO JWST surveys

Characterising the prevalence and properties of faint active galactic nuclei (AGN) in the early Universe is key for understanding the formation of supermassive black holes (SMBHs) and determining their role in cosmic reionization. We perform a spectroscopic search for broad H$α$ emitters at $z\approx4-6$ using deep JWST/NIRCam imaging and wide field slitless spectroscopy from the EIGER and FRESCO surveys. We identify 20 H$α$ lines at $z=4.2-5.5$ that have broad components with line widths from $\sim1200-3700$ km s$^{-1}$, contributing $\sim30-90$ % of the total line flux. We interpret these broad components as being powered by accretion onto SMBHs with implied masses $\sim10^{7-8}$ M$_{\odot}$. In the UV luminosity range M$_{\rm UV}=-21$ to $-18$, we measure number densities of $\approx10^{-5}$ cMpc$^{-3}$. This is an order of magnitude higher than expected from extrapolating quasar UV luminosity functions. Yet, such AGN are found in only $<1$ % of star-forming galaxies at $z\sim5$. The SMBH mass function agrees with large cosmological simulations. In two objects we detect narrow red- and blue-shifted H$α$ absorption indicative, respectively, of dense gas fueling SMBH growth and outflows. We may be witnessing early AGN feedback that will clear dust-free pathways through which more massive blue quasars are seen. We uncover a strong correlation between reddening and the fraction of total galaxy luminosity arising from faint AGN. This implies that early SMBH growth is highly obscured and that faint AGN are only minor contributors to cosmic reionization.

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arXiv2024

A small and vigorous black hole in the early Universe

Multiple theories have been proposed to describe the formation of black hole seeds in the early Universe and to explain the emergence of very massive black holes observed in the first billion years after Big Bang. Models consider different seeding and accretion scenarios, which require the detection and characterisation of black holes in the first few hundred million years after Big Bang to be validated. Here we present an extensive analysis of the JWST-NIRSpec spectrum of GN-z11, an exceptionally luminous galaxy at z=10.6, revealing the detection of the [NeIV]2423 and CII*1335 transitions (typical of Active Galactic Nuclei, AGN), as well as semi-forbidden nebular lines tracing gas densities higher than 10^9 cm-3, typical of the Broad Line Region of AGN. These spectral features indicate that GN-z11 hosts an accreting black hole. The spectrum also reveals a deep and blueshifted CIV1549 absorption trough, tracing an outflow with velocity 800-1000 km/s, likely driven by the AGN. Assuming local virial relations, we derive a black hole mass of log(M_BH/Msun) = 6.2 +- 0.3, accreting at about 5 times the Eddington rate. These properties are consistent with both heavy seeds scenarios, or scenarios envisaging intermediate/light seeds experiencing episodic super-Eddington phases. Our finding naturally explains the high luminosity of GN-z11 and can also provide an explanation for its exceptionally high nitrogen abundance.

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arXiv2023

The galaxies missed by Hubble and ALMA: the contribution of extremely red galaxies to the cosmic census at 3<z<8

Using deep JWST imaging from JADES, JEMS and SMILES, we characterize optically-faint and extremely red galaxies at $z>3$ that were previously missing from galaxy census estimates. The data indicate the existence of abundant, dusty and post-starburst-like galaxies down to $10^8$M$_\odot$, below the sensitivity limit of Spitzer and ALMA. Modeling the NIRCam and HST photometry of these red sources can result in extreme, high values for both stellar mass and star formation rate (SFR); however, including 7 MIRI filters out to 21$μ$m results in decreased mass (median 0.6 dex for log$_{10}$M$^*$/M$_{\odot}>$10), and SFR (median 10$\times$ for SFR$>$100 M$_{\odot}$/yr). At $z>6$, our sample includes a high fraction of little red dots (LRDs; NIRCam-selected dust-reddened AGN candidates). We significantly measure older stellar populations in the LRDs out to rest-frame 3$μ$m (the stellar bump) and rule out a dominant contribution from hot dust emission, a signature of AGN contamination to stellar population measurements. This allows us to measure their contribution to the cosmic census at $z>3$, below the typical detection limits of ALMA ($L_{\rm IR}<10^{12}L_\odot$). We find that these sources, which are overwhelmingly missed by HST and ALMA, could effectively double the obscured fraction of the star formation rate density at $4<z<6$ compared to some estimates, showing that prior to JWST, the obscured contribution from fainter sources could be underestimated. Finally, we identify five sources with evidence for Balmer breaks and high stellar masses at $5.5<z<7.7$. While spectroscopy is required to determine their nature, we discuss possible measurement systematics to explore with future data.

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arXiv2023

JADES: Resolving the Stellar Component and Filamentary Overdense Environment of HST-Dark Submillimeter Galaxy HDF850.1 at $z=5.18$

HDF850.1 is the brightest submillimeter galaxy (SMG) in the Hubble Deep Field. It is known as a heavily dust-obscured star-forming galaxy embedded in an overdense environment at $z = 5.18$. With nine-band NIRCam images at 0.8-5.0 $μ$m obtained through the JWST Advanced Deep Extragalactic Survey (JADES), we detect and resolve the rest-frame UV-optical counterpart of HDF850.1, which splits into two components because of heavy dust obscuration in the center. The southern component leaks UV and H$α$ photons, bringing the galaxy $\sim$100 times above the empirical relation between infrared excess and UV continuum slope (IRX-$β_\mathrm{UV}$). The northern component is higher in dust attenuation and thus fainter in UV and H$α$ surface brightness. We construct a spatially resolved dust attenuation map from the NIRCam images, well matched with the dust continuum emission obtained through millimeter interferometry. The whole system hosts a stellar mass of $10^{10.8\pm0.1}\,\mathrm{M}_\odot$ and star-formation rate of $10^{2.8\pm0.2}\,\mathrm{M}_\odot\,\mathrm{yr}^{-1}$, placing the galaxy at the massive end of the star-forming main sequence at this epoch. We further confirm that HDF850.1 resides in a complex overdense environment at $z=5.17-5.30$, which hosts another luminous SMG at $z=5.30$ (GN10). The filamentary structures of the overdensity are characterized by 109 H$α$-emitting galaxies confirmed through NIRCam slitless spectroscopy at 3.9-5 $μ$m, of which only eight were known before the JWST observations. Given the existence of a similar galaxy overdensity in the GOODS-S field, our results suggest that $50\pm20$% of the cosmic star formation at $z=5.1-5.5$ occur in protocluster environments.

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arXiv2023

FRESCO: An extended, massive, rapidly rotating galaxy at z=5.3

With the remarkable sensitivity and resolution of JWST in the infrared, measuring rest-optical kinematics of galaxies at $z>5$ has become possible for the first time. This study pilots a new method for measuring galaxy dynamics for highly multiplexed, unbiased samples by combining FRESCO NIRCam grism spectroscopy and JADES medium-band imaging. Here we present one of the first JWST kinematic measurements for a galaxy at $z>5$. We find a significant velocity gradient, which, if interpreted as rotation yields $V_{rot} = 240\pm50$km/s and we hence refer to this galaxy as Twister-z5. With a rest-frame optical effective radius of $r_e=2.25$kpc, the high rotation velocity in this galaxy is not due to a compact size as may be expected in the early universe but rather a high total mass, ${\rm log(M}_{dyn}/{\rm M}_\odot)=11.0\pm0.2$. This is a factor of roughly 4x higher than the stellar mass within the effective radius. We also observe that the radial H$α$ equivalent width profile and the specific star formation rate map from resolved stellar population modeling is centrally depressed by a factor of $\sim1.5$ from the center to $r_e$. Combined with the morphology of the line-emitting gas in comparison to the continuum, this centrally suppressed star formation is consistent with a star-forming disk surrounding a bulge growing inside-out. While large, rapidly rotating disks are common to z~2, the existence of one after only 1Gyr of cosmic time, shown for the first time in ionized gas, adds to the growing evidence that some galaxies matured earlier than expected in the history of the universe.

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arXiv2023

Exploring the Correlation between $\rm{H}α$-to-UV Ratio and Burstiness for Typical Star-forming Galaxies at $z\sim2$

The $\rm{H}α$-to-UV luminosity ratio ($L(\rm Hα)/L(\rm UV)$) is often used to probe SFHs of star-forming galaxies and it is important to validate it against other proxies for burstiness. To address this issue, we present a statistical analysis of the resolved distribution of $Σ_{\rm{SFR}}$ as well as stellar age and their correlations with the globally measured $L(\rm Hα)/L(\rm UV)$ for a sample of 310 star-forming galaxies in two redshift bins of $1.37 < z < 1.70$ and $ 2.09 < z < 2.61$ observed by the MOSDEF survey. We use the multi-waveband CANDELS/3D-HST imaging of MOSDEF galaxies to construct $Σ_{\rm{SFR}}$ and stellar age maps. We analyze the composite rest-frame far-UV spectra of a subsample of MOSDEF targets obtained by the Keck/LRIS, which includes 124 star-forming galaxies (MOSDEF-LRIS) at redshifts $1.4 < z < 2.6$, to examine the average stellar population properties, and the strength of age-sensitive FUV spectral features in bins of $L(\rm Hα)/L(\rm UV)$. Our results show no significant evidence that individual galaxies with higher $L(\rm Hα)/L(\rm UV)$ are undergoing a burst of star formation based on the resolved distribution of $Σ_{\rm{SFR}}$ of individual star-forming galaxies. We segregate the sample into subsets with low and high $L(\rm Hα)/L(\rm UV)$. The high-$L(\rm Hα)/L(\rm UV)$ subset exhibits, on average, an age of $\log[\rm{Age/yr}]$ = 8.0, compared to $\log[\rm{Age/yr}]$ = 8.4 for the low-$L(\rm Hα)/L(\rm UV)$ galaxies, though the difference in age is significant at only the $2σ$ level. Furthermore, we find no variation in the strengths of Siiv$λ\lambda1393, 1402$ and Civ$λ\lambda1548, 1550$ P-Cygni features from massive stars between the two subsamples.

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arXiv2023

JADES: Discovery of extremely high equivalent width Lyman-alpha emission from a faint galaxy within an ionized bubble at z=7.3

We report the discovery of a remarkable Ly$α$ emitting galaxy at z = 7.2782, JADES-GS-z7-LA, with EW$_0$(Ly$α$) $= 388.0 \pm 88.8$Åand UV magnitude -17.0. The spectroscopic redshift is confirmed via rest-frame optical lines [O II], H$β$ and [O III] in its JWST/NIRSpec Micro-Shutter Assembly (MSA) spectrum. The Ly$α$ line is detected in both lower resolution PRISM as well as medium resolution G140M grating spectra. The LSF-deconvolved Ly$α$ FWHM in the grating is $383.9 \pm 56.2$ km/s and the Ly$α$ velocity offset compared to the systemic redshift is $113.3 \pm 80.0$ km/s, indicative of very little neutral gas or dust within the galaxy. We estimate the Ly$α$ escape fraction to be >70%. JADES-GS-z7-LA has a O32 ratio of $11.1 \pm 2.2$ and a R23 ratio of $11.2 \pm 2.6$, consistent with low metallicity and high ionization parameters. Deep NIRCam imaging also revealed a close companion source (separated by 0.23"), which exhibits similar photometry to that of JADES-GS-z7-LA, with a photometric excess in the F410M NIRCam image consistent with [O III]+H$β$ emission at the same redshift. The spectral energy distribution of JADES-GS-z7-LA indicates a "bursty" star formation history, with a low stellar mass of $\approx 10^7$ $M_\odot$. Assuming that the Ly$α$ transmission through the intergalactic medium is the same as its measured escape fraction, an ionized region of size > 1.5 pMpc is needed to explain the high Ly$α$ EW and low velocity offset compared to systemic seen in JADES-GS-z7-LA. Owing to its UV-faintness, we show that it is incapable of single-handedly ionizing a region large enough to explain its Ly$α$ emission. Therefore, we suggest that JADES-GS-z7-LA (and possibly the companion source) may be a part of a larger overdensity, presenting direct evidence of overlapping ionized bubbles at $z>7$.

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arXiv2023

JADES: Insights on the low-mass end of the mass--metallicity--star-formation rate relation at $3 < z < 10$ from deep JWST/NIRSpec spectroscopy

We analyse the gas-phase metallicity properties of a sample of low stellar mass (log M*/M_sun <= 9) galaxies at 3 < z < 10, observed with JWST/NIRSpec as part of the JADES programme in its deep GOODS-S tier. By combining this sample with more massive galaxies at similar redshifts from other programmes, we study the scaling relations between stellar mass, oxygen abundance (O/H), and star-formation rate (SFR) for 146 galaxies, spanning across three orders of magnitude in stellar mass and out to the epoch of early galaxy assembly. We find evidence for a shallower slope at the low-mass-end of the mass-metallicity relation (MZR), with 12 + log(O/H) = (7.72+-0.02) + (0.17+-0.03) log(M* / 10^8 M_sun), in good agreement with the MZR probed by local analogues of high-redshift systems like 'Green Pea' and 'Blueberry' galaxies. The inferred slope is well matched by models including 'momentum-driven' SNe winds, suggesting that feedback mechanisms in dwarf galaxies (and at high-z) might be different from those in place at higher masses. The evolution in the normalisation is observed to be relatively mild compared to previous determinations of the MZR at z~3 (~ 0.1 - 0.2 dex across the explored mass regime). We observe a deviation from the local fundamental metallicity relation (FMR) for our sample at high redshift, especially at z > 6, with galaxies significantly less enriched (with a median offset in log(O/H) of ~ 0.5 dex, significant at ~ 5 sigma) than predicted given their M* and SFR. These observations are consistent with an enhanced stochasticity in the star-formation history, and/or with an increased efficiency in metal removals by outflows, prompting us to reconsider the nature of the relationship between M*, O/H, and SFR in the early Universe.

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arXiv2023

Mapping dusty galaxy growth at $z>5$ with FRESCO: Detection of H$α$ in submm galaxy HDF850.1 and the surrounding overdense structures

We report the detection of a 13$σ$ H$α$ emission line from HDF850.1 at $z=5.188\pm0.001$ using the FRESCO NIRCam F444W grism observations. Detection of H$α$ in HDF850.1 is noteworthy, given its high far-IR luminosity, substantial dust obscuration, and the historical challenges in deriving its redshift. HDF850.1 shows a clear detection in the F444W imaging data, distributed between a northern and southern component, mirroring that seen in [CII] from the Plateau de Bure Interferometer. Modeling the SED of each component separately, we find that the northern component has a higher mass, star formation rate (SFR), and dust extinction than the southern component. The observed H$α$ emission appears to arise entirely from the less-obscured southern component and shows a similar $Δ$v$\sim$+130 km/s velocity offset to that seen for [CII] relative to the source systemic redshift. Leveraging H$α$-derived redshifts from FRESCO observations, we find that HDF850.1 is forming in one of the richest environments identified to date at $z>5$, with 100 $z=5.17-5.20$ galaxies distributed across 10 structures and a $\sim$(15 cMpc)$^3$ volume. Based on the evolution of analogous structures in cosmological simulations, the $z=5.17-5.20$ structures seem likely to collapse into a single $>$10$^{14}$ $M_{\odot}$ cluster by $z\sim0$. Comparing galaxy properties forming within this overdensity with those outside, we find the masses, SFRs, and $UV$ luminosities inside the overdensity to be clearly higher. The prominence of H$α$ line emission from HDF850.1 and other known highly-obscured $z>5$ galaxies illustrates the potential of NIRCam-grism programs to map both the early build-up of IR-luminous galaxies and overdense structures.

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arXiv2023

JADES Initial Data Release for the Hubble Ultra Deep Field: Revealing the Faint Infrared Sky with Deep JWST NIRCam Imaging

JWST has revolutionized the field of extragalactic astronomy with its sensitive and high-resolution infrared view of the distant universe. Adding to the new legacy of JWST observations, we present the first NIRCam imaging data release from the JWST Advanced Deep Extragalactic Survey (JADES) providing 9 filters of infrared imaging of $\sim$25 arcmin$^2$ covering the Hubble Ultra Deep Field and portions of Great Observatories Origins Deep Survey (GOODS) South. Utilizing 87 on-sky dual-filter hours of exposure time, these images reveal the deepest ever near-infrared view of this iconic field. We supply carefully constructed 9-band mosaics of the JADES bands, as well as matching reductions of 5 additional bands from the JWST Extragalactic Medium-band Survey (JEMS). Combining with existing HST imaging, we provide 23-band space-based photometric catalogs and photometric redshifts for $\approx47,500$ sources. To promote broad engagement with the JADES survey, we have created an interactive {\tt FitsMap} website to provide an interface for professional researchers and the public to experience these JWST datasets. Combined with the first JADES NIRSpec data release, these public JADES imaging and spectroscopic datasets provide a new foundation for discoveries of the infrared universe by the worldwide scientific community.

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